1604642640 has 160 divisors (see below), whose sum is σ = 5150027520. Its totient is φ = 412987392.

The previous prime is 1604642639. The next prime is 1604642659. The reversal of 1604642640 is 462464061.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1215901 + ... + 1217219.

It is an arithmetic number, because the mean of its divisors is an integer number (32187672).

Almost surely, 2^1604642640 is an apocalyptic number.

1604642640 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 1604642640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2575013760).

1604642640 is an abundant number, since it is smaller than the sum of its proper divisors (3545384880).

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

1604642640 is a wasteful number, since it uses less digits than its factorization.

1604642640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1509 (or 1503 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 33.

The square root of 1604642640 is about 40057.9909631025. The cubic root of 1604642640 is about 1170.7372663447.

The spelling of 1604642640 in words is "one billion, six hundred four million, six hundred forty-two thousand, six hundred forty".