645640270 has 48 divisors (see below), whose sum is σ = 1307219760. Its totient is φ = 229299840.

The previous prime is 645640249. The next prime is 645640351. The reversal of 645640270 is 72046546.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a congruent 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, 45826 + ... + 58234.

It is an arithmetic number, because the mean of its divisors is an integer number (27233745).

Almost surely, 2^645640270 is an apocalyptic number.

645640270 is an abundant number, since it is smaller than the sum of its proper divisors (661579490).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645640270 is a wasteful number, since it uses less digits than its factorization.

645640270 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12481 (or 12470 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 34.

The square root of 645640270 is about 25409.4523750513. The cubic root of 645640270 is about 864.2980572814.

The spelling of 645640270 in words is "six hundred forty-five million, six hundred forty thousand, two hundred seventy".