81235975 has 18 divisors (see below), whose sum is σ = 102991424. Its totient is φ = 63562800.

The previous prime is 81235951. The next prime is 81235991. The reversal of 81235975 is 57953218.

It is not a de Polignac number, because 81235975 - 2⁵ = 81235943 is a prime.

It is a Duffinian number.

Its product of digits (75600) is a multiple of the sum of its prime factors (1575).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 54490 + ... + 55960.

Almost surely, 2^81235975 is an apocalyptic number.

81235975 is a deficient number, since it is larger than the sum of its proper divisors (21755449).

81235975 is a wasteful number, since it uses less digits than its factorization.

81235975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1575 (or 1523 counting only the distinct ones).

The product of its digits is 75600, while the sum is 40.

The square root of 81235975 is about 9013.1001880596. The cubic root of 81235975 is about 433.0946302037.

The spelling of 81235975 in words is "eighty-one million, two hundred thirty-five thousand, nine hundred seventy-five".