668650320 has 120 divisors (see below), whose sum is σ = 2418319176. Its totient is φ = 164588544.

The previous prime is 668650277. The next prime is 668650321. The reversal of 668650320 is 23056866.

It can be written as a sum of positive squares in 4 ways, for example, as 47444544 + 621205776 = 6888^2 + 24924^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×668650320² = 894186500872204800, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668650321) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26359 + ... + 45078.

Almost surely, 2^668650320 is an apocalyptic number.

668650320 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

668650320 is an abundant number, since it is smaller than the sum of its proper divisors (1749668856).

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

668650320 is a wasteful number, since it uses less digits than its factorization.

668650320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71469 (or 71460 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 668650320 is about 25858.2737242841. The cubic root of 668650320 is about 874.4460471958.

The spelling of 668650320 in words is "six hundred sixty-eight million, six hundred fifty thousand, three hundred twenty".