18975881 has 2 divisors, whose sum is σ = 18975882. Its totient is φ = 18975880.

The previous prime is 18975871. The next prime is 18975967. The reversal of 18975881 is 18857981.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18361225 + 614656 = 4285^2 + 784^2 .

It is a cyclic number.

It is not a de Polignac number, because 18975881 - 2²² = 14781577 is a prime.

It is a super-2 number, since 2×18975881² = 720168119452322, which contains 22 as substring.

It is a Chen prime.

It is a pancake number, because a pancake can be divided into 18975881 parts by 6160 straight cuts.

It is not a weakly prime, because it can be changed into another prime (18975811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9487940 + 9487941.

It is an arithmetic number, because the mean of its divisors is an integer number (9487941).

Almost surely, 2^18975881 is an apocalyptic number.

It is an amenable number.

18975881 is a deficient number, since it is larger than the sum of its proper divisors (1).

18975881 is an equidigital number, since it uses as much as digits as its factorization.

18975881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 161280, while the sum is 47.

The square root of 18975881 is about 4356.1314259329. The cubic root of 18975881 is about 266.7272062203.

The spelling of 18975881 in words is "eighteen million, nine hundred seventy-five thousand, eight hundred eighty-one".