669624681 has 32 divisors (see below), whose sum is σ = 999820800. Its totient is φ = 395136000.

The previous prime is 669624677. The next prime is 669624719. The reversal of 669624681 is 186426966.

It is a happy number.

It is not a de Polignac number, because 669624681 - 2² = 669624677 is a prime.

It is a super-2 number, since 2×669624681² = 896794426808703522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 669624681.

It is not an unprimeable number, because it can be changed into a prime (669624601) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 636606 + ... + 637656.

It is an arithmetic number, because the mean of its divisors is an integer number (31244400).

Almost surely, 2^669624681 is an apocalyptic number.

It is an amenable number.

669624681 is a deficient number, since it is larger than the sum of its proper divisors (330196119).

669624681 is a wasteful number, since it uses less digits than its factorization.

669624681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1557.

The product of its digits is 746496, while the sum is 48.

The square root of 669624681 is about 25877.1072765099. The cubic root of 669624681 is about 874.8705902766.

The spelling of 669624681 in words is "six hundred sixty-nine million, six hundred twenty-four thousand, six hundred eighty-one".