81613902 has 32 divisors (see below), whose sum is σ = 167795712. Its totient is φ = 26451104.

The previous prime is 81613901. The next prime is 81613907. The reversal of 81613902 is 20931618.

It is a self number, because there is not a number n which added to its sum of digits gives 81613902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81613901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46228 + ... + 47960.

It is an arithmetic number, because the mean of its divisors is an integer number (5243616).

Almost surely, 2^81613902 is an apocalyptic number.

81613902 is an abundant number, since it is smaller than the sum of its proper divisors (86181810).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81613902 is a wasteful number, since it uses less digits than its factorization.

81613902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1952.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 81613902 is about 9034.0412883714. The cubic root of 81613902 is about 433.7652074385.

The spelling of 81613902 in words is "eighty-one million, six hundred thirteen thousand, nine hundred two".