666859974 has 64 divisors (see below), whose sum is σ = 1491125760. Its totient is φ = 197120000.

The previous prime is 666859937. The next prime is 666859979. The reversal of 666859974 is 479958666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666859979) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 472582 + ... + 473990.

It is an arithmetic number, because the mean of its divisors is an integer number (23298840).

Almost surely, 2^666859974 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666859974, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (745562880).

666859974 is an abundant number, since it is smaller than the sum of its proper divisors (824265786).

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

666859974 is a wasteful number, since it uses less digits than its factorization.

666859974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1597.

The product of its digits is 19595520, while the sum is 60.

The square root of 666859974 is about 25823.6320838104. The cubic root of 666859974 is about 873.6648913317.

The spelling of 666859974 in words is "six hundred sixty-six million, eight hundred fifty-nine thousand, nine hundred seventy-four".