646540263156654 has 24 divisors (see below), whose sum is σ = 1408171463217792. Its totient is φ = 214385078532480.

The previous prime is 646540263156647. The next prime is 646540263156659. The reversal of 646540263156654 is 456651362045646.

646540263156654 is a `hidden beast` number, since 6 + 4 + 6 + 5 + 4 + 0 + 2 + 63 + 1 + 566 + 5 + 4 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 646540263156591 and 646540263156600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646540263156659) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 94028539779 + ... + 94028546654.

It is an arithmetic number, because the mean of its divisors is an integer number (58673810967408).

Almost surely, 2^{646540263156654} is an apocalyptic number.

646540263156654 is an abundant number, since it is smaller than the sum of its proper divisors (761631200061138).

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

646540263156654 is a wasteful number, since it uses less digits than its factorization.

646540263156654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188057086632 (or 188057086629 counting only the distinct ones).

The product of its (nonzero) digits is 373248000, while the sum is 63.

The spelling of 646540263156654 in words is "six hundred forty-six trillion, five hundred forty billion, two hundred sixty-three million, one hundred fifty-six thousand, six hundred fifty-four".