97978881 has 96 divisors (see below), whose sum is σ = 183859200. Its totient is φ = 45601920.

The previous prime is 97978831. The next prime is 97978891. The reversal of 97978881 is 18887979.

It is not a de Polignac number, because 97978881 - 2¹⁷ = 97847809 is a prime.

It is a super-2 number, since 2×97978881² = 19199722244024322, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97978831) 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 95 ways as a sum of consecutive naturals, for example, 1240200 + ... + 1240278.

It is an arithmetic number, because the mean of its divisors is an integer number (1915200).

Almost surely, 2^97978881 is an apocalyptic number.

97978881 is a gapful number since it is divisible by the number (91) formed by its first and last digit.

It is an amenable number.

97978881 is a deficient number, since it is larger than the sum of its proper divisors (85880319).

97978881 is a wasteful number, since it uses less digits than its factorization.

97978881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179 (or 172 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 57.

The square root of 97978881 is about 9898.4282085592. The cubic root of 97978881 is about 461.0105085259.

The spelling of 97978881 in words is "ninety-seven million, nine hundred seventy-eight thousand, eight hundred eighty-one".