1640173820 has 24 divisors (see below), whose sum is σ = 3445291584. Its totient is φ = 655893056.

The previous prime is 1640173813. The next prime is 1640173831. The reversal of 1640173820 is 283710461.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85997 + ... + 103323.

It is an arithmetic number, because the mean of its divisors is an integer number (143553816).

Almost surely, 2^1640173820 is an apocalyptic number.

1640173820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1640173820 is an abundant number, since it is smaller than the sum of its proper divisors (1805117764).

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

1640173820 is a wasteful number, since it uses less digits than its factorization.

1640173820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22069 (or 22067 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 1640173820 is about 40499.0594952525. The cubic root of 1640173820 is about 1179.3153693995.

The spelling of 1640173820 in words is "one billion, six hundred forty million, one hundred seventy-three thousand, eight hundred twenty".