97977681 has 20 divisors (see below), whose sum is σ = 154973412. Its totient is φ = 61475328.

The previous prime is 97977679. The next prime is 97977683. The reversal of 97977681 is 18677979.

It is an interprime number because it is at equal distance from previous prime (97977679) and next prime (97977683).

It can be written as a sum of positive squares in 2 ways, for example, as 35820225 + 62157456 = 5985^2 + 7884^2 .

It is not a de Polignac number, because 97977681 - 2¹ = 97977679 is a prime.

It is a super-2 number, since 2×97977681² = 19199251948275522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (97977683) 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 19 ways as a sum of consecutive naturals, for example, 34200 + ... + 36953.

Almost surely, 2^97977681 is an apocalyptic number.

It is an amenable number.

97977681 is a deficient number, since it is larger than the sum of its proper divisors (56995731).

97977681 is a wasteful number, since it uses less digits than its factorization.

97977681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71182 (or 71173 counting only the distinct ones).

The product of its digits is 1333584, while the sum is 54.

The square root of 97977681 is about 9898.3675926892. The cubic root of 97977681 is about 461.0086264370.

The spelling of 97977681 in words is "ninety-seven million, nine hundred seventy-seven thousand, six hundred eighty-one".