81619630 has 32 divisors (see below), whose sum is σ = 159991200. Its totient is φ = 29860992.

The previous prime is 81619613. The next prime is 81619723. The reversal of 81619630 is 3691618.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1897 + ... + 12916.

It is an arithmetic number, because the mean of its divisors is an integer number (4999725).

Almost surely, 2^81619630 is an apocalyptic number.

81619630 is a deficient number, since it is larger than the sum of its proper divisors (78371570).

81619630 is a wasteful number, since it uses less digits than its factorization.

81619630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14868.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 81619630 is about 9034.3583059341. The cubic root of 81619630 is about 433.7753550111.

The spelling of 81619630 in words is "eighty-one million, six hundred nineteen thousand, six hundred thirty".