647816256 has 42 divisors (see below), whose sum is σ = 1856849982. Its totient is φ = 215938560.

The previous prime is 647816251. The next prime is 647816317. The reversal of 647816256 is 652618746.

It can be written as a sum of positive squares in only one way, i.e., 508953600 + 138862656 = 22560^2 + 11784^2 .

It is not an unprimeable number, because it can be changed into a prime (647816251) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 561765 + ... + 562916.

Almost surely, 2^647816256 is an apocalyptic number.

It is an amenable number.

647816256 is an abundant number, since it is smaller than the sum of its proper divisors (1209033726).

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

647816256 is a wasteful number, since it uses less digits than its factorization.

647816256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1124699 (or 1124686 counting only the distinct ones).

The product of its digits is 483840, while the sum is 45.

The square root of 647816256 is about 25452.2347938251. The cubic root of 647816256 is about 865.2679428768.

The spelling of 647816256 in words is "six hundred forty-seven million, eight hundred sixteen thousand, two hundred fifty-six".