12540881 has 2 divisors, whose sum is σ = 12540882. Its totient is φ = 12540880.

The previous prime is 12540877. The next prime is 12540937. The reversal of 12540881 is 18804521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11833600 + 707281 = 3440^2 + 841^2 .

It is an emirp because it is prime and its reverse (18804521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12540881 - 2² = 12540877 is a prime.

It is a super-2 number, since 2×12540881² = 314547392512322, which contains 22 as substring.

It is equal to p₈₂₁₁₈₉ and since 12540881 and 821189 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (12540811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6270440 + 6270441.

It is an arithmetic number, because the mean of its divisors is an integer number (6270441).

Almost surely, 2^12540881 is an apocalyptic number.

It is an amenable number.

12540881 is a deficient number, since it is larger than the sum of its proper divisors (1).

12540881 is an equidigital number, since it uses as much as digits as its factorization.

12540881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2560, while the sum is 29.

The square root of 12540881 is about 3541.3106330849. The cubic root of 12540881 is about 232.3321700903.

The spelling of 12540881 in words is "twelve million, five hundred forty thousand, eight hundred eighty-one".