12155881 has 2 divisors, whose sum is σ = 12155882. Its totient is φ = 12155880.

The previous prime is 12155863. The next prime is 12155893. The reversal of 12155881 is 18855121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9211225 + 2944656 = 3035^2 + 1716^2 .

It is a cyclic number.

It is not a de Polignac number, because 12155881 - 2⁵ = 12155849 is a prime.

It is a super-2 number, since 2×12155881² = 295530885772322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12155821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6077940 + 6077941.

It is an arithmetic number, because the mean of its divisors is an integer number (6077941).

Almost surely, 2^12155881 is an apocalyptic number.

It is an amenable number.

12155881 is a deficient number, since it is larger than the sum of its proper divisors (1).

12155881 is an equidigital number, since it uses as much as digits as its factorization.

12155881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3200, while the sum is 31.

The square root of 12155881 is about 3486.5285026800. The cubic root of 12155881 is about 229.9299156345.

The spelling of 12155881 in words is "twelve million, one hundred fifty-five thousand, eight hundred eighty-one".