1640000 has 70 divisors (see below), whose sum is σ = 4165854. Its totient is φ = 640000.

The previous prime is 1639999. The next prime is 1640017. The reversal of 1640000 is 461.

It can be written as a sum of positive squares in 5 ways, for example, as 1098304 + 541696 = 1048^2 + 736^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 39980 + ... + 40020.

2^1640000 is an apocalyptic number.

1640000 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 1640000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2082927).

1640000 is an abundant number, since it is smaller than the sum of its proper divisors (2525854).

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

1640000 is an frugal number, since it uses more digits than its factorization.

1640000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73 (or 48 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 1640000 is about 1280.6248474866. The cubic root of 1640000 is about 117.9273707994.

Adding to 1640000 its reverse (461), we get a palindrome (1640461).

It can be divided in two parts, 16 and 40000, that multiplied together give a square (640000 = 800²).

The spelling of 1640000 in words is "one million, six hundred forty thousand".