645036278 has 24 divisors (see below), whose sum is σ = 990653976. Its totient is φ = 314978720.

The previous prime is 645036247. The next prime is 645036307. The reversal of 645036278 is 872630546.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1381001 + ... + 1381467.

It is an arithmetic number, because the mean of its divisors is an integer number (41277249).

Almost surely, 2^645036278 is an apocalyptic number.

645036278 is a deficient number, since it is larger than the sum of its proper divisors (345617698).

645036278 is a wasteful number, since it uses less digits than its factorization.

645036278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 748 (or 677 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 41.

The square root of 645036278 is about 25397.5644107855. The cubic root of 645036278 is about 864.0284582462.

The spelling of 645036278 in words is "six hundred forty-five million, thirty-six thousand, two hundred seventy-eight".