660812587 has 4 divisors (see below), whose sum is σ = 666660600. Its totient is φ = 654964576.

The previous prime is 660812557. The next prime is 660812591. The reversal of 660812587 is 785218066.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-660812587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (660812557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2923837 + ... + 2924062.

It is an arithmetic number, because the mean of its divisors is an integer number (166665150).

Almost surely, 2^660812587 is an apocalyptic number.

660812587 is a deficient number, since it is larger than the sum of its proper divisors (5848013).

660812587 is a wasteful number, since it uses less digits than its factorization.

660812587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5848012.

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 660812587 is about 25706.2752455505. The cubic root of 660812587 is about 871.0159387361.

The spelling of 660812587 in words is "six hundred sixty million, eight hundred twelve thousand, five hundred eighty-seven".