92721681 has 18 divisors (see below), whose sum is σ = 145028598. Its totient is φ = 57058560.

The previous prime is 92721677. The next prime is 92721683. The reversal of 92721681 is 18612729.

It can be written as a sum of positive squares in 3 ways, for example, as 11451456 + 81270225 = 3384^2 + 9015^2 .

It is not a de Polignac number, because 92721681 - 2² = 92721677 is a prime.

It is a super-2 number, since 2×92721681² = 17194620254931522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (92721683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 28960 + ... + 32001.

Almost surely, 2^92721681 is an apocalyptic number.

It is an amenable number.

92721681 is a deficient number, since it is larger than the sum of its proper divisors (52306917).

92721681 is a wasteful number, since it uses less digits than its factorization.

92721681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60993 (or 60977 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 92721681 is about 9629.2097806622. The cubic root of 92721681 is about 452.6130783807.

The spelling of 92721681 in words is "ninety-two million, seven hundred twenty-one thousand, six hundred eighty-one".