660988 has 6 divisors (see below), whose sum is σ = 1156736. Its totient is φ = 330492.

The previous prime is 660983. The next prime is 661009. The reversal of 660988 is 889066.

It is a super-2 number, since 2×660988² = 873810272288, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82620 + ... + 82627.

2⁶⁶⁰⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

660988 is a deficient number, since it is larger than the sum of its proper divisors (495748).

660988 is a wasteful number, since it uses less digits than its factorization.

660988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165251 (or 165249 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 660988 is about 813.0116850329. The cubic root of 660988 is about 87.1093002443.

The spelling of 660988 in words is "six hundred sixty thousand, nine hundred eighty-eight".