1640407654656 has 81 divisors (see below), whose sum is σ = 4729876936239. Its totient is φ = 546782059008.

The previous prime is 1640407654651. The next prime is 1640407654681. The reversal of 1640407654656 is 6564567040461.

The square root of 1640407654656 is 1280784.

It is a perfect power (a square), and thus also a powerful number.

1640407654656 is a `hidden beast` number, since 1 + 6 + 4 + 0 + 40 + 7 + 6 + 546 + 56 = 666.

It is not an unprimeable number, because it can be changed into a prime (1640407654651) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 61464291 + ... + 61490973.

Almost surely, 2^{1640407654656} is an apocalyptic number.

1640407654656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

1640407654656 is the 1280784-th square number.

It is an amenable number.

1640407654656 is an abundant number, since it is smaller than the sum of its proper divisors (3089469281583).

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

1640407654656 is an frugal number, since it uses more digits than its factorization.

1640407654656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53388 (or 26688 counting only the distinct ones).

The product of its (nonzero) digits is 14515200, while the sum is 54.

The spelling of 1640407654656 in words is "one trillion, six hundred forty billion, four hundred seven million, six hundred fifty-four thousand, six hundred fifty-six".