669942624 has 96 divisors (see below), whose sum is σ = 1940216544. Its totient is φ = 201093120.

The previous prime is 669942619. The next prime is 669942649. The reversal of 669942624 is 426249966.

It is a happy number.

669942624 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

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, 44622 + ... + 57714.

It is an arithmetic number, because the mean of its divisors is an integer number (20210589).

Almost surely, 2^669942624 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 669942624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (970108272).

669942624 is an abundant number, since it is smaller than the sum of its proper divisors (1270273920).

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

669942624 is a wasteful number, since it uses less digits than its factorization.

669942624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13160 (or 13152 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 48.

The square root of 669942624 is about 25883.2498732288. The cubic root of 669942624 is about 875.0090334850.

The spelling of 669942624 in words is "six hundred sixty-nine million, nine hundred forty-two thousand, six hundred twenty-four".