645868961496 has 128 divisors (see below), whose sum is σ = 1972119916800. Its totient is φ = 194223744000.

The previous prime is 645868961461. The next prime is 645868961537. The reversal of 645868961496 is 694169868546.

645868961496 is a `hidden beast` number, since 6 + 4 + 58 + 6 + 89 + 6 + 1 + 496 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 726265 + ... + 1348776.

It is an arithmetic number, because the mean of its divisors is an integer number (15407186850).

Almost surely, 2^645868961496 is an apocalyptic number.

645868961496 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

645868961496 is an abundant number, since it is smaller than the sum of its proper divisors (1326250955304).

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

645868961496 is a wasteful number, since it uses less digits than its factorization.

645868961496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2075198 (or 2075188 counting only the distinct ones).

The product of its digits is 537477120, while the sum is 72.

The spelling of 645868961496 in words is "six hundred forty-five billion, eight hundred sixty-eight million, nine hundred sixty-one thousand, four hundred ninety-six".