660537687 has 4 divisors (see below), whose sum is σ = 880716920. Its totient is φ = 440358456.

The previous prime is 660537649. The next prime is 660537697. The reversal of 660537687 is 786735066.

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

It is not a de Polignac number, because 660537687 - 2⁶ = 660537623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660537697) 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, 110089612 + ... + 110089617.

It is an arithmetic number, because the mean of its divisors is an integer number (220179230).

Almost surely, 2^660537687 is an apocalyptic number.

660537687 is a deficient number, since it is larger than the sum of its proper divisors (220179233).

660537687 is a wasteful number, since it uses less digits than its factorization.

660537687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220179232.

The product of its (nonzero) digits is 1270080, while the sum is 48.

The square root of 660537687 is about 25700.9277459005. The cubic root of 660537687 is about 870.8951402441.

The spelling of 660537687 in words is "six hundred sixty million, five hundred thirty-seven thousand, six hundred eighty-seven".