81976737 has 32 divisors (see below), whose sum is σ = 119048832. Its totient is φ = 49987584.

The previous prime is 81976721. The next prime is 81976747. The reversal of 81976737 is 73767918.

It is a happy number.

It is not a de Polignac number, because 81976737 - 2⁴ = 81976721 is a prime.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (81976717) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 361018 + ... + 361244.

It is an arithmetic number, because the mean of its divisors is an integer number (3720276).

Almost surely, 2^81976737 is an apocalyptic number.

It is an amenable number.

81976737 is a deficient number, since it is larger than the sum of its proper divisors (37072095).

81976737 is a wasteful number, since it uses less digits than its factorization.

81976737 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417.

The product of its digits is 444528, while the sum is 48.

The square root of 81976737 is about 9054.1005627285. The cubic root of 81976737 is about 434.4070610843.

The spelling of 81976737 in words is "eighty-one million, nine hundred seventy-six thousand, seven hundred thirty-seven".