81675237 has 32 divisors (see below), whose sum is σ = 128765952. Its totient is φ = 45082944.

The previous prime is 81675233. The next prime is 81675241. The reversal of 81675237 is 73257618.

It is an interprime number because it is at equal distance from previous prime (81675233) and next prime (81675241).

It is not a de Polignac number, because 81675237 - 2² = 81675233 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81675195 and 81675204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81675233) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 81423 + ... + 82419.

It is an arithmetic number, because the mean of its divisors is an integer number (4023936).

Almost surely, 2^81675237 is an apocalyptic number.

It is an amenable number.

81675237 is a deficient number, since it is larger than the sum of its proper divisors (47090715).

81675237 is a wasteful number, since it uses less digits than its factorization.

81675237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1137.

The product of its digits is 70560, while the sum is 39.

The square root of 81675237 is about 9037.4353109718. The cubic root of 81675237 is about 433.8738422272.

The spelling of 81675237 in words is "eighty-one million, six hundred seventy-five thousand, two hundred thirty-seven".