645947502 has 16 divisors (see below), whose sum is σ = 1348064640. Its totient is φ = 205954232.

The previous prime is 645947473. The next prime is 645947509. The reversal of 645947502 is 205749546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645947509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2340252 + ... + 2340527.

It is an arithmetic number, because the mean of its divisors is an integer number (84254040).

Almost surely, 2^645947502 is an apocalyptic number.

645947502 is an abundant number, since it is smaller than the sum of its proper divisors (702117138).

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

645947502 is a wasteful number, since it uses less digits than its factorization.

645947502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4680807.

The product of its (nonzero) digits is 302400, while the sum is 42.

The square root of 645947502 is about 25415.4972802029. The cubic root of 645947502 is about 864.4351294378.

The spelling of 645947502 in words is "six hundred forty-five million, nine hundred forty-seven thousand, five hundred two".