81364913 has 8 divisors (see below), whose sum is σ = 93360960. Its totient is φ = 69462000.

The previous prime is 81364891. The next prime is 81364919. The reversal of 81364913 is 31946318.

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 81364913 - 2¹⁶ = 81299377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81364919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21398 + ... + 24911.

It is an arithmetic number, because the mean of its divisors is an integer number (11670120).

Almost surely, 2^81364913 is an apocalyptic number.

It is an amenable number.

81364913 is a deficient number, since it is larger than the sum of its proper divisors (11996047).

81364913 is a wasteful number, since it uses less digits than its factorization.

81364913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46567.

The product of its digits is 15552, while the sum is 35.

The square root of 81364913 is about 9020.2501628281. The cubic root of 81364913 is about 433.3236454770.

The spelling of 81364913 in words is "eighty-one million, three hundred sixty-four thousand, nine hundred thirteen".