666977280 has 176 divisors, whose sum is σ = 2154164544. Its totient is φ = 176128000.

The previous prime is 666977251. The next prime is 666977287. The reversal of 666977280 is 82779666.

It is not an unprimeable number, because it can be changed into a prime (666977287) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2657155 + ... + 2657405.

Almost surely, 2^666977280 is an apocalyptic number.

666977280 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 666977280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1077082272).

666977280 is an abundant number, since it is smaller than the sum of its proper divisors (1487187264).

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

666977280 is a wasteful number, since it uses less digits than its factorization.

666977280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452 (or 434 counting only the distinct ones).

The product of its (nonzero) digits is 1524096, while the sum is 51.

The square root of 666977280 is about 25825.9032755875. The cubic root of 666977280 is about 873.7161165409.

The spelling of 666977280 in words is "six hundred sixty-six million, nine hundred seventy-seven thousand, two hundred eighty".