660642440 has 48 divisors (see below), whose sum is σ = 1579054500. Its totient is φ = 248708096.

The previous prime is 660642431. The next prime is 660642473. The reversal of 660642440 is 44246066.

It can be written as a sum of positive squares in 6 ways, for example, as 272316004 + 388326436 = 16502^2 + 19706^2 .

It is a junction number, because it is equal to n+sod(n) for n = 660642397 and 660642406.

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, 17015 + ... + 40134.

Almost surely, 2^660642440 is an apocalyptic number.

It is an amenable number.

660642440 is an abundant number, since it is smaller than the sum of its proper divisors (918412060).

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

660642440 is a wasteful number, since it uses less digits than its factorization.

660642440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57194 (or 57173 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 32.

The square root of 660642440 is about 25702.9655876516. The cubic root of 660642440 is about 870.9411754960.

The spelling of 660642440 in words is "six hundred sixty million, six hundred forty-two thousand, four hundred forty".