81876531 has 8 divisors (see below), whose sum is σ = 119093184. Its totient is φ = 49622120.

The previous prime is 81876499. The next prime is 81876551. The reversal of 81876531 is 13567818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81876531 - 2⁵ = 81876499 is a prime.

It is a super-2 number, since 2×81876531² = 13407532657187922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81876531.

It is not an unprimeable number, because it can be changed into a prime (81876551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1240521 + ... + 1240586.

It is an arithmetic number, because the mean of its divisors is an integer number (14886648).

Almost surely, 2^81876531 is an apocalyptic number.

81876531 is a deficient number, since it is larger than the sum of its proper divisors (37216653).

81876531 is a wasteful number, since it uses less digits than its factorization.

81876531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2481121.

The product of its digits is 40320, while the sum is 39.

The square root of 81876531 is about 9048.5651348708. The cubic root of 81876531 is about 434.2299866919.

The spelling of 81876531 in words is "eighty-one million, eight hundred seventy-six thousand, five hundred thirty-one".