81308635 has 4 divisors (see below), whose sum is σ = 97570368. Its totient is φ = 65046904.

The previous prime is 81308621. The next prime is 81308653. The reversal of 81308635 is 53680318.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81308635 - 2¹⁷ = 81177563 is a prime.

It is a super-2 number, since 2×81308635² = 13222188251126450, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81308635.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8130859 + ... + 8130868.

It is an arithmetic number, because the mean of its divisors is an integer number (24392592).

Almost surely, 2^81308635 is an apocalyptic number.

81308635 is a deficient number, since it is larger than the sum of its proper divisors (16261733).

81308635 is a wasteful number, since it uses less digits than its factorization.

81308635 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16261732.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 81308635 is about 9017.1300866739. The cubic root of 81308635 is about 433.2237161918.

The spelling of 81308635 in words is "eighty-one million, three hundred eight thousand, six hundred thirty-five".