661023975 has 12 divisors (see below), whose sum is σ = 1092893096. Its totient is φ = 352546080.

The previous prime is 661023953. The next prime is 661023983. The reversal of 661023975 is 579320166.

It is not a de Polignac number, because 661023975 - 2⁶ = 661023911 is a prime.

It is a Duffinian number.

It is a congruent number.

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, 4406752 + ... + 4406901.

Almost surely, 2^661023975 is an apocalyptic number.

661023975 is a deficient number, since it is larger than the sum of its proper divisors (431869121).

661023975 is a wasteful number, since it uses less digits than its factorization.

661023975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8813666 (or 8813661 counting only the distinct ones).

The product of its (nonzero) digits is 68040, while the sum is 39.

The square root of 661023975 is about 25710.3865198484. The cubic root of 661023975 is about 871.1088055546.

The spelling of 661023975 in words is "six hundred sixty-one million, twenty-three thousand, nine hundred seventy-five".