668641824 has 96 divisors (see below), whose sum is σ = 2064968640. Its totient is φ = 209765376.

The previous prime is 668641819. The next prime is 668641849. The reversal of 668641824 is 428146866.

It is a tau number, because it is divible by the number of its divisors (96).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 668641824.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8074 + ... + 37449.

It is an arithmetic number, because the mean of its divisors is an integer number (21510090).

Almost surely, 2^668641824 is an apocalyptic number.

It is an amenable number.

668641824 is an abundant number, since it is smaller than the sum of its proper divisors (1396326816).

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

668641824 is a wasteful number, since it uses less digits than its factorization.

668641824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45559 (or 45545 counting only the distinct ones).

The product of its digits is 442368, while the sum is 45.

The square root of 668641824 is about 25858.1094436542. The cubic root of 668641824 is about 874.4423435533.

The spelling of 668641824 in words is "six hundred sixty-eight million, six hundred forty-one thousand, eight hundred twenty-four".