645020626 has 16 divisors (see below), whose sum is σ = 1019662560. Its totient is φ = 305173440.

The previous prime is 645020617. The next prime is 645020669. The reversal of 645020626 is 626020546.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23845 + ... + 43111.

It is an arithmetic number, because the mean of its divisors is an integer number (63728910).

Almost surely, 2^645020626 is an apocalyptic number.

645020626 is a deficient number, since it is larger than the sum of its proper divisors (374641934).

645020626 is a wasteful number, since it uses less digits than its factorization.

645020626 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20169.

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 645020626 is about 25397.2562691327. The cubic root of 645020626 is about 864.0214695525.

The spelling of 645020626 in words is "six hundred forty-five million, twenty thousand, six hundred twenty-six".