666873936 has 60 divisors (see below), whose sum is σ = 1878906900. Its totient is φ = 220792320.

The previous prime is 666873923. The next prime is 666873967. The reversal of 666873936 is 639378666.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 133263936 + 533610000 = 11544^2 + 23100^2 .

It is a super-2 number, since 2×666873936² = 889441693032264192, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5916 + ... + 36996.

It is an arithmetic number, because the mean of its divisors is an integer number (31315115).

Almost surely, 2^666873936 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 666873936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (939453450).

666873936 is an abundant number, since it is smaller than the sum of its proper divisors (1212032964).

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

666873936 is a wasteful number, since it uses less digits than its factorization.

666873936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31244 (or 31235 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 54.

The square root of 666873936 is about 25823.9024161725. The cubic root of 666873936 is about 873.6709885758.

The spelling of 666873936 in words is "six hundred sixty-six million, eight hundred seventy-three thousand, nine hundred thirty-six".