81630290975 has 6 divisors (see below), whose sum is σ = 101221560840. Its totient is φ = 65304232760.

The previous prime is 81630290939. The next prime is 81630291031. The reversal of 81630290975 is 57909203618.

It is a de Polignac number, because none of the positive numbers 2^k-81630290975 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1632605795 + ... + 1632605844.

It is an arithmetic number, because the mean of its divisors is an integer number (16870260140).

Almost surely, 2^81630290975 is an apocalyptic number.

81630290975 is a deficient number, since it is larger than the sum of its proper divisors (19591269865).

81630290975 is a wasteful number, since it uses less digits than its factorization.

81630290975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3265211649 (or 3265211644 counting only the distinct ones).

The product of its (nonzero) digits is 816480, while the sum is 50.

The spelling of 81630290975 in words is "eighty-one billion, six hundred thirty million, two hundred ninety thousand, nine hundred seventy-five".