1647138656 has 48 divisors (see below), whose sum is σ = 3304240128. Its totient is φ = 808080000.

The previous prime is 1647138643. The next prime is 1647138659. The reversal of 1647138656 is 6568317461.

It is a self number, because there is not a number n which added to its sum of digits gives 1647138656.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1647138659) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 505031 + ... + 508281.

It is an arithmetic number, because the mean of its divisors is an integer number (68838336).

Almost surely, 2^1647138656 is an apocalyptic number.

1647138656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1647138656 is an abundant number, since it is smaller than the sum of its proper divisors (1657101472).

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

1647138656 is a wasteful number, since it uses less digits than its factorization.

1647138656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3555 (or 3547 counting only the distinct ones).

The product of its digits is 725760, while the sum is 47.

The square root of 1647138656 is about 40584.9560305293. The cubic root of 1647138656 is about 1180.9822941922.

The spelling of 1647138656 in words is "one billion, six hundred forty-seven million, one hundred thirty-eight thousand, six hundred fifty-six".