12512435881 has 9 divisors (see below), whose sum is σ = 13754691223. Its totient is φ = 11373823120.

The previous prime is 12512435879. The next prime is 12512435893. The reversal of 12512435881 is 18853421521.

The square root of 12512435881 is 111859.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 11694475881 + 817960000 = 108141^2 + 28600^2 .

It is not a de Polignac number, because 12512435881 - 2¹ = 12512435879 is a prime.

It is a super-2 number, since 2×12512435881² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12512435581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1225365 + ... + 1235533.

Almost surely, 2^12512435881 is an apocalyptic number.

12512435881 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

12512435881 is the 111859-th square number.

12512435881 is the 55930-th centered octagonal number.

It is an amenable number.

12512435881 is a deficient number, since it is larger than the sum of its proper divisors (1242255342).

12512435881 is an frugal number, since it uses more digits than its factorization.

12512435881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20360 (or 10180 counting only the distinct ones).

The product of its digits is 76800, while the sum is 40.

The spelling of 12512435881 in words is "twelve billion, five hundred twelve million, four hundred thirty-five thousand, eight hundred eighty-one".