645636078 has 24 divisors (see below), whose sum is σ = 1421813016. Its totient is φ = 211683600.

The previous prime is 645636073. The next prime is 645636083. The reversal of 645636078 is 870636546.

645636078 is a `hidden beast` number, since 6 + 4 + 5 + 636 + 0 + 7 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (645636073) and next prime (645636083).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645636071) 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, 292908 + ... + 295103.

It is an arithmetic number, because the mean of its divisors is an integer number (59242209).

Almost surely, 2^645636078 is an apocalyptic number.

645636078 is an abundant number, since it is smaller than the sum of its proper divisors (776176938).

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

645636078 is a wasteful number, since it uses less digits than its factorization.

645636078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 588080 (or 588077 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The square root of 645636078 is about 25409.3698859299. The cubic root of 645636078 is about 864.2961867118.

The spelling of 645636078 in words is "six hundred forty-five million, six hundred thirty-six thousand, seventy-eight".