81613113 has 8 divisors (see below), whose sum is σ = 114544800. Its totient is φ = 51545088.

The previous prime is 81613079. The next prime is 81613117. The reversal of 81613113 is 31131618.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81613113 - 2²⁰ = 80564537 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81613117) 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, 715848 + ... + 715961.

It is an arithmetic number, because the mean of its divisors is an integer number (14318100).

Almost surely, 2^81613113 is an apocalyptic number.

It is an amenable number.

81613113 is a deficient number, since it is larger than the sum of its proper divisors (32931687).

81613113 is a wasteful number, since it uses less digits than its factorization.

81613113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1431831.

The product of its digits is 432, while the sum is 24.

The square root of 81613113 is about 9033.9976201015. The cubic root of 81613113 is about 433.7638096299.

The spelling of 81613113 in words is "eighty-one million, six hundred thirteen thousand, one hundred thirteen".