645646830 has 32 divisors (see below), whose sum is σ = 1552307328. Its totient is φ = 171866400.

The previous prime is 645646829. The next prime is 645646831. The reversal of 645646830 is 38646546.

It is an interprime number because it is at equal distance from previous prime (645646829) and next prime (645646831).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645646831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1716 + ... + 35975.

It is an arithmetic number, because the mean of its divisors is an integer number (48509604).

Almost surely, 2^645646830 is an apocalyptic number.

645646830 is an abundant number, since it is smaller than the sum of its proper divisors (906660498).

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

645646830 is a wasteful number, since it uses less digits than its factorization.

645646830 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38272.

The product of its (nonzero) digits is 414720, while the sum is 42.

The square root of 645646830 is about 25409.5814605436. The cubic root of 645646830 is about 864.3009844925.

The spelling of 645646830 in words is "six hundred forty-five million, six hundred forty-six thousand, eight hundred thirty".