666793620 has 120 divisors (see below), whose sum is σ = 2098418784. Its totient is φ = 177246144.

The previous prime is 666793597. The next prime is 666793637. The reversal of 666793620 is 26397666.

It is a super-2 number, since 2×666793620² = 889227463345408800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 846867 + ... + 847653.

Almost surely, 2^666793620 is an apocalyptic number.

666793620 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 666793620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1049209392).

666793620 is an abundant number, since it is smaller than the sum of its proper divisors (1431625164).

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

666793620 is a wasteful number, since it uses less digits than its factorization.

666793620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1331 (or 1320 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 45.

The square root of 666793620 is about 25822.3472984158. The cubic root of 666793620 is about 873.6359131927.

The spelling of 666793620 in words is "six hundred sixty-six million, seven hundred ninety-three thousand, six hundred twenty".