97891191 has 24 divisors (see below), whose sum is σ = 144418560. Its totient is φ = 63882000.

The previous prime is 97891147. The next prime is 97891193. The reversal of 97891191 is 19119879.

It is not a de Polignac number, because 97891191 - 2¹⁴ = 97874807 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97891193) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 92616 + ... + 93666.

It is an arithmetic number, because the mean of its divisors is an integer number (6017440).

Almost surely, 2^97891191 is an apocalyptic number.

97891191 is a deficient number, since it is larger than the sum of its proper divisors (46527369).

97891191 is a wasteful number, since it uses less digits than its factorization.

97891191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1267 (or 1264 counting only the distinct ones).

The product of its digits is 40824, while the sum is 45.

The square root of 97891191 is about 9893.9977258942. The cubic root of 97891191 is about 460.8729343964.

Adding to 97891191 its sum of digits (45), we get a square (97891236 = 9894²).

The spelling of 97891191 in words is "ninety-seven million, eight hundred ninety-one thousand, one hundred ninety-one".