97890181 has 4 divisors (see below), whose sum is σ = 97941292. Its totient is φ = 97839072.

The previous prime is 97890161. The next prime is 97890187. The reversal of 97890181 is 18109879.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 81162081 + 16728100 = 9009^2 + 4090^2 .

It is a cyclic number.

It is not a de Polignac number, because 97890181 - 2⁹ = 97889669 is a prime.

It is a super-3 number, since 3×97890181³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (97890187) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22566 + ... + 26551.

It is an arithmetic number, because the mean of its divisors is an integer number (24485323).

Almost surely, 2^97890181 is an apocalyptic number.

It is an amenable number.

97890181 is a deficient number, since it is larger than the sum of its proper divisors (51111).

97890181 is a wasteful number, since it uses less digits than its factorization.

97890181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51110.

The product of its (nonzero) digits is 36288, while the sum is 43.

The square root of 97890181 is about 9893.9466847159. The cubic root of 97890181 is about 460.8713493602.

The spelling of 97890181 in words is "ninety-seven million, eight hundred ninety thousand, one hundred eighty-one".