136421531 has 2 divisors, whose sum is σ = 136421532. Its totient is φ = 136421530.

The previous prime is 136421521. The next prime is 136421563. The reversal of 136421531 is 135124631.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-136421531 is a prime.

It is a super-2 number, since 2×136421531² = 37221668240767922, which contains 22 as substring.

It is a Sophie Germain 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 136421531.

It is not a weakly prime, because it can be changed into another prime (136421521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68210765 + 68210766.

It is an arithmetic number, because the mean of its divisors is an integer number (68210766).

Almost surely, 2^136421531 is an apocalyptic number.

136421531 is a deficient number, since it is larger than the sum of its proper divisors (1).

136421531 is an equidigital number, since it uses as much as digits as its factorization.

136421531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 26.

The square root of 136421531 is about 11679.9627995983. The cubic root of 136421531 is about 514.7870813688.

The spelling of 136421531 in words is "one hundred thirty-six million, four hundred twenty-one thousand, five hundred thirty-one".