81499113 has 12 divisors (see below), whose sum is σ = 123917040. Its totient is φ = 51473016.

The previous prime is 81499063. The next prime is 81499133. The reversal of 81499113 is 31199418.

It is not a de Polignac number, because 81499113 - 2¹⁰ = 81498089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81499133) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 238131 + ... + 238472.

It is an arithmetic number, because the mean of its divisors is an integer number (10326420).

Almost surely, 2^81499113 is an apocalyptic number.

It is an amenable number.

81499113 is a deficient number, since it is larger than the sum of its proper divisors (42417927).

81499113 is a wasteful number, since it uses less digits than its factorization.

81499113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 476628 (or 476625 counting only the distinct ones).

The product of its digits is 7776, while the sum is 36.

The square root of 81499113 is about 9027.6859161138. The cubic root of 81499113 is about 433.5617501225.

The spelling of 81499113 in words is "eighty-one million, four hundred ninety-nine thousand, one hundred thirteen".