669718020 has 24 divisors (see below), whose sum is σ = 1875210624. Its totient is φ = 178591456.

The previous prime is 669717943. The next prime is 669718031. The reversal of 669718020 is 20817966.

It is a self number, because there is not a number n which added to its sum of digits gives 669718020.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5580924 + ... + 5581043.

It is an arithmetic number, because the mean of its divisors is an integer number (78133776).

Almost surely, 2^669718020 is an apocalyptic number.

669718020 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

669718020 is an abundant number, since it is smaller than the sum of its proper divisors (1205492604).

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

669718020 is a wasteful number, since it uses less digits than its factorization.

669718020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11161979 (or 11161977 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 39.

The square root of 669718020 is about 25878.9107189619. The cubic root of 669718020 is about 874.9112377988.

The spelling of 669718020 in words is "six hundred sixty-nine million, seven hundred eighteen thousand, twenty".