666952811520 has 352 divisors, whose sum is σ = 2154633028608. Its totient is φ = 176077504512.

The previous prime is 666952811509. The next prime is 666952811533. The reversal of 666952811520 is 25118259666.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1219291887 + ... + 1219292433.

Almost surely, 2^666952811520 is an apocalyptic number.

666952811520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666952811520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1077316514304).

666952811520 is an abundant number, since it is smaller than the sum of its proper divisors (1487680217088).

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

666952811520 is a wasteful number, since it uses less digits than its factorization.

666952811520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1225 (or 1207 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 51.

The spelling of 666952811520 in words is "six hundred sixty-six billion, nine hundred fifty-two million, eight hundred eleven thousand, five hundred twenty".