131121409 has 2 divisors, whose sum is σ = 131121410. Its totient is φ = 131121408.

The previous prime is 131121379. The next prime is 131121433. The reversal of 131121409 is 904121131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 91393600 + 39727809 = 9560^2 + 6303^2 .

It is a cyclic number.

It is not a de Polignac number, because 131121409 - 2⁷ = 131121281 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 131121409.

It is not a weakly prime, because it can be changed into another prime (131121439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65560704 + 65560705.

It is an arithmetic number, because the mean of its divisors is an integer number (65560705).

Almost surely, 2^131121409 is an apocalyptic number.

It is an amenable number.

131121409 is a deficient number, since it is larger than the sum of its proper divisors (1).

131121409 is an equidigital number, since it uses as much as digits as its factorization.

131121409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 131121409 is about 11450.8256907526. The cubic root of 131121409 is about 508.0321566537.

The spelling of 131121409 in words is "one hundred thirty-one million, one hundred twenty-one thousand, four hundred nine".