645106370 has 16 divisors (see below), whose sum is σ = 1161571320. Its totient is φ = 257958144.

The previous prime is 645106333. The next prime is 645106381. The reversal of 645106370 is 73601546.

It can be written as a sum of positive squares in 4 ways, for example, as 354983281 + 290123089 = 18841^2 + 17033^2 .

It is a super-2 number, since 2×645106370² = 832324457229153800, which contains 22 as substring.

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, 28394 + ... + 45786.

Almost surely, 2^645106370 is an apocalyptic number.

645106370 is a deficient number, since it is larger than the sum of its proper divisors (516464950).

645106370 is a wasteful number, since it uses less digits than its factorization.

645106370 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21109.

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 645106370 is about 25398.9442693983. The cubic root of 645106370 is about 864.0597532763.

The spelling of 645106370 in words is "six hundred forty-five million, one hundred six thousand, three hundred seventy".