131556769 has 2 divisors, whose sum is σ = 131556770. Its totient is φ = 131556768.

The previous prime is 131556767. The next prime is 131556791. The reversal of 131556769 is 967655131.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 91929744 + 39627025 = 9588^2 + 6295^2 .

It is a cyclic number.

It is not a de Polignac number, because 131556769 - 2¹ = 131556767 is a prime.

It is a super-2 number, since 2×131556769² = 34614366939438722, which contains 22 as substring.

Together with 131556767, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (131556767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65778384 + 65778385.

It is an arithmetic number, because the mean of its divisors is an integer number (65778385).

Almost surely, 2^131556769 is an apocalyptic number.

It is an amenable number.

131556769 is a deficient number, since it is larger than the sum of its proper divisors (1).

131556769 is an equidigital number, since it uses as much as digits as its factorization.

131556769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 170100, while the sum is 43.

The square root of 131556769 is about 11469.8199201208. The cubic root of 131556769 is about 508.5938054394.

The spelling of 131556769 in words is "one hundred thirty-one million, five hundred fifty-six thousand, seven hundred sixty-nine".