81999962 has 16 divisors (see below), whose sum is σ = 134713152. Its totient is φ = 37125120.

The previous prime is 81999961. The next prime is 81999971. The reversal of 81999962 is 26999918.

It is not an unprimeable number, because it can be changed into a prime (81999961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1598 + ... + 12905.

It is an arithmetic number, because the mean of its divisors is an integer number (8419572).

Almost surely, 2^81999962 is an apocalyptic number.

81999962 is a deficient number, since it is larger than the sum of its proper divisors (52713190).

81999962 is a wasteful number, since it uses less digits than its factorization.

81999962 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14773.

The product of its digits is 629856, while the sum is 53.

The square root of 81999962 is about 9055.3830399382. The cubic root of 81999962 is about 434.4480814670.

The spelling of 81999962 in words is "eighty-one million, nine hundred ninety-nine thousand, nine hundred sixty-two".