645772548681624 has 256 divisors, whose sum is σ = 2070513185126400. Its totient is φ = 163240455426048.

The previous prime is 645772548681607. The next prime is 645772548681641. The reversal of 645772548681624 is 426186845277546.

It is an interprime number because it is at equal distance from previous prime (645772548681607) and next prime (645772548681641).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 28534572 + ... + 45888635.

It is an arithmetic number, because the mean of its divisors is an integer number (8087942129400).

Almost surely, 2^{645772548681624} is an apocalyptic number.

It is an amenable number.

645772548681624 is an abundant number, since it is smaller than the sum of its proper divisors (1424740636444776).

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

645772548681624 is a wasteful number, since it uses less digits than its factorization.

645772548681624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74423402 (or 74423398 counting only the distinct ones).

The product of its digits is 4335206400, while the sum is 75.

The spelling of 645772548681624 in words is "six hundred forty-five trillion, seven hundred seventy-two billion, five hundred forty-eight million, six hundred eighty-one thousand, six hundred twenty-four".