669021980 has 48 divisors (see below), whose sum is σ = 1547894880. Its totient is φ = 240864000.

The previous prime is 669021937. The next prime is 669022019. The reversal of 669021980 is 89120966.

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, 7166 + ... + 37274.

It is an arithmetic number, because the mean of its divisors is an integer number (32247810).

Almost surely, 2^669021980 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 669021980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (773947440).

669021980 is an abundant number, since it is smaller than the sum of its proper divisors (878872900).

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

669021980 is a wasteful number, since it uses less digits than its factorization.

669021980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30230 (or 30228 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 41.

The square root of 669021980 is about 25865.4592072130. The cubic root of 669021980 is about 874.6080334198.

The spelling of 669021980 in words is "six hundred sixty-nine million, twenty-one thousand, nine hundred eighty".