1640169000 has 160 divisors (see below), whose sum is σ = 5733585000. Its totient is φ = 437356800.

The previous prime is 1640168989. The next prime is 1640169029. The reversal of 1640169000 is 9610461.

1640169000 is a `hidden beast` number, since 1 + 640 + 16 + 9 + 0 + 0 + 0 = 666.

It is a Cunningham number, because it is equal to 40499²-1.

It can be written as a sum of positive squares in 4 ways, for example, as 332478756 + 1307690244 = 18234^2 + 36162^2 .

It is a super-2 number, since 2×1640169000² = 5380308697122000000, which contains 22 as substring.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 70876 + ... + 91124.

Almost surely, 2^1640169000 is an apocalyptic number.

1640169000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1640169000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2866792500).

1640169000 is an abundant number, since it is smaller than the sum of its proper divisors (4093416000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1640169000 is a wasteful number, since it uses less digits than its factorization.

1640169000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20282 (or 20259 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 1640169000 is about 40498.9999876540. Note that the first 4 decimals coincide. The cubic root of 1640169000 is about 1179.3142141752.

Adding to 1640169000 its reverse (9610461), we get a palindrome (1649779461).

The spelling of 1640169000 in words is "one billion, six hundred forty million, one hundred sixty-nine thousand".