81635996 has 12 divisors (see below), whose sum is σ = 153852552. Its totient is φ = 37678128.

The previous prime is 81635959. The next prime is 81636017. The reversal of 81635996 is 69953618.

It is a self number, because there is not a number n which added to its sum of digits gives 81635996.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 784910 + ... + 785013.

It is an arithmetic number, because the mean of its divisors is an integer number (12821046).

Almost surely, 2^81635996 is an apocalyptic number.

It is an amenable number.

81635996 is a deficient number, since it is larger than the sum of its proper divisors (72216556).

81635996 is a wasteful number, since it uses less digits than its factorization.

81635996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1569940 (or 1569938 counting only the distinct ones).

The product of its digits is 349920, while the sum is 47.

The square root of 81635996 is about 9035.2640249192. The cubic root of 81635996 is about 433.8043459659.

The spelling of 81635996 in words is "eighty-one million, six hundred thirty-five thousand, nine hundred ninety-six".