1131521437 has 2 divisors, whose sum is σ = 1131521438. Its totient is φ = 1131521436.

The previous prime is 1131521423. The next prime is 1131521441. The reversal of 1131521437 is 7341251311.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 604864836 + 526656601 = 24594^2 + 22949^2 .

It is a cyclic number.

It is not a de Polignac number, because 1131521437 - 2²⁷ = 997303709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1131521407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 565760718 + 565760719.

It is an arithmetic number, because the mean of its divisors is an integer number (565760719).

Almost surely, 2^1131521437 is an apocalyptic number.

It is an amenable number.

1131521437 is a deficient number, since it is larger than the sum of its proper divisors (1).

1131521437 is an equidigital number, since it uses as much as digits as its factorization.

1131521437 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 28.

The square root of 1131521437 is about 33638.0950263239. The cubic root of 1131521437 is about 1042.0476905019.

Adding to 1131521437 its reverse (7341251311), we get a palindrome (8472772748).

The spelling of 1131521437 in words is "one billion, one hundred thirty-one million, five hundred twenty-one thousand, four hundred thirty-seven".