81249976 has 8 divisors (see below), whose sum is σ = 152343720. Its totient is φ = 40624984.

The previous prime is 81249943. The next prime is 81249979. The reversal of 81249976 is 67994218.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81249979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5078116 + ... + 5078131.

It is an arithmetic number, because the mean of its divisors is an integer number (19042965).

Almost surely, 2^81249976 is an apocalyptic number.

It is an amenable number.

81249976 is a deficient number, since it is larger than the sum of its proper divisors (71093744).

81249976 is a wasteful number, since it uses less digits than its factorization.

81249976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10156253 (or 10156249 counting only the distinct ones).

The product of its digits is 217728, while the sum is 46.

The square root of 81249976 is about 9013.8768573794. The cubic root of 81249976 is about 433.1195100248.

The spelling of 81249976 in words is "eighty-one million, two hundred forty-nine thousand, nine hundred seventy-six".