2521131881 has 4 divisors (see below), whose sum is σ = 2521236564. Its totient is φ = 2521027200.

The previous prime is 2521131859. The next prime is 2521131883. The reversal of 2521131881 is 1881311252.

2521131881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 664814656 + 1856317225 = 25784^2 + 43085^2 .

It is a cyclic number.

It is not a de Polignac number, because 2521131881 - 2²⁶ = 2454023017 is a prime.

It is a super-2 number, since 2×2521131881² = 12712211922789196322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2521131883) 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, 4001 + ... + 71121.

It is an arithmetic number, because the mean of its divisors is an integer number (630309141).

Almost surely, 2^2521131881 is an apocalyptic number.

It is an amenable number.

2521131881 is a deficient number, since it is larger than the sum of its proper divisors (104683).

2521131881 is an equidigital number, since it uses as much as digits as its factorization.

2521131881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104682.

The product of its digits is 3840, while the sum is 32.

The square root of 2521131881 is about 50210.8741310087. The cubic root of 2521131881 is about 1361.0221340325.

The spelling of 2521131881 in words is "two billion, five hundred twenty-one million, one hundred thirty-one thousand, eight hundred eighty-one".