81371313 has 12 divisors (see below), whose sum is σ = 118463488. Its totient is φ = 53819640.

The previous prime is 81371261. The next prime is 81371317. The reversal of 81371313 is 31317318.

It is not a de Polignac number, because 81371313 - 2⁹ = 81370801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81371317) 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, 34453 + ... + 36738.

Almost surely, 2^81371313 is an apocalyptic number.

It is an amenable number.

81371313 is a deficient number, since it is larger than the sum of its proper divisors (37092175).

81371313 is a wasteful number, since it uses less digits than its factorization.

81371313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71324 (or 71321 counting only the distinct ones).

The product of its digits is 1512, while the sum is 27.

The square root of 81371313 is about 9020.6049131973. The cubic root of 81371313 is about 433.3350066339.

The spelling of 81371313 in words is "eighty-one million, three hundred seventy-one thousand, three hundred thirteen".