97981551 has 12 divisors (see below), whose sum is σ = 141705928. Its totient is φ = 65239344.

The previous prime is 97981547. The next prime is 97981553. The reversal of 97981551 is 15518979.

97981551 is a `hidden beast` number, since 9 + 7 + 98 + 1 + 551 = 666.

It is not a de Polignac number, because 97981551 - 2² = 97981547 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 97981497 and 97981506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97981553) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1296 + ... + 14058.

Almost surely, 2^97981551 is an apocalyptic number.

97981551 is a deficient number, since it is larger than the sum of its proper divisors (43724377).

97981551 is a wasteful number, since it uses less digits than its factorization.

97981551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13622 (or 13619 counting only the distinct ones).

The product of its digits is 113400, while the sum is 45.

The square root of 97981551 is about 9898.5630775381. The cubic root of 97981551 is about 461.0146961183.

The spelling of 97981551 in words is "ninety-seven million, nine hundred eighty-one thousand, five hundred fifty-one".