645256570 has 16 divisors (see below), whose sum is σ = 1327385088. Its totient is φ = 221230800.

The previous prime is 645256567. The next prime is 645256603. The reversal of 645256570 is 75652546.

It is a super-2 number, since 2×645256570² = 832712082256329800, 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, 4608906 + ... + 4609045.

It is an arithmetic number, because the mean of its divisors is an integer number (82961568).

Almost surely, 2^645256570 is an apocalyptic number.

645256570 is an abundant number, since it is smaller than the sum of its proper divisors (682128518).

645256570 is a wasteful number, since it uses less digits than its factorization.

645256570 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9217965.

The product of its (nonzero) digits is 252000, while the sum is 40.

The square root of 645256570 is about 25401.9009131207. The cubic root of 645256570 is about 864.1268076981.

The spelling of 645256570 in words is "six hundred forty-five million, two hundred fifty-six thousand, five hundred seventy".