646913970 has 24 divisors (see below), whose sum is σ = 1681976556. Its totient is φ = 172510368.

The previous prime is 646913807. The next prime is 646913999. The reversal of 646913970 is 79319646.

It can be written as a sum of positive squares in 2 ways, for example, as 641254329 + 5659641 = 25323^2 + 2379^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3593877 + ... + 3594056.

Almost surely, 2^646913970 is an apocalyptic number.

646913970 is an abundant number, since it is smaller than the sum of its proper divisors (1035062586).

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

646913970 is a wasteful number, since it uses less digits than its factorization.

646913970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7187946 (or 7187943 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 646913970 is about 25434.5035335860. The cubic root of 646913970 is about 864.8660378152.

The spelling of 646913970 in words is "six hundred forty-six million, nine hundred thirteen thousand, nine hundred seventy".