645505355 has 24 divisors (see below), whose sum is σ = 865434192. Its totient is φ = 461736000.

The previous prime is 645505321. The next prime is 645505387. The reversal of 645505355 is 553505546.

645505355 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 645505355 - 2⁸ = 645505099 is a prime.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28160 + ... + 45650.

It is an arithmetic number, because the mean of its divisors is an integer number (36059758).

Almost surely, 2^645505355 is an apocalyptic number.

645505355 is a deficient number, since it is larger than the sum of its proper divisors (219928837).

645505355 is a wasteful number, since it uses less digits than its factorization.

645505355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17579 (or 17568 counting only the distinct ones).

The product of its (nonzero) digits is 225000, while the sum is 38.

The square root of 645505355 is about 25406.7974172268. The cubic root of 645505355 is about 864.2378509504.

The spelling of 645505355 in words is "six hundred forty-five million, five hundred five thousand, three hundred fifty-five".