81413313 has 4 divisors (see below), whose sum is σ = 108551088. Its totient is φ = 54275540.

The previous prime is 81413303. The next prime is 81413327. The reversal of 81413313 is 31331418.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81413313 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81413303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13568883 + ... + 13568888.

It is an arithmetic number, because the mean of its divisors is an integer number (27137772).

Almost surely, 2^81413313 is an apocalyptic number.

It is an amenable number.

81413313 is a deficient number, since it is larger than the sum of its proper divisors (27137775).

81413313 is a wasteful number, since it uses less digits than its factorization.

81413313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27137774.

The product of its digits is 864, while the sum is 24.

The square root of 81413313 is about 9022.9326163947. The cubic root of 81413313 is about 433.4095494475.

The spelling of 81413313 in words is "eighty-one million, four hundred thirteen thousand, three hundred thirteen".