669049956 has 63 divisors (see below), whose sum is σ = 1759125571. Its totient is φ = 222551064.

The previous prime is 669049939. The next prime is 669049987. The reversal of 669049956 is 659940966.

It is a happy number.

The square root of 669049956 is 25866.

It is a perfect power (a square), and thus also a powerful number.

669049956 is a `hidden beast` number, since 66 + 90 + 499 + 5 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 1396525 + ... + 1397003.

Almost surely, 2^669049956 is an apocalyptic number.

669049956 is the 25866-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 669049956

669049956 is an abundant number, since it is smaller than the sum of its proper divisors (1090075615).

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

669049956 is an frugal number, since it uses more digits than its factorization.

669049956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980 (or 484 counting only the distinct ones).

The product of its (nonzero) digits is 3149280, while the sum is 54.

The cubic root of 669049956 is about 874.6202241968.

The spelling of 669049956 in words is "six hundred sixty-nine million, forty-nine thousand, nine hundred fifty-six".