136871521 has 2 divisors, whose sum is σ = 136871522. Its totient is φ = 136871520.

The previous prime is 136871513. The next prime is 136871533. The reversal of 136871521 is 125178631.

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., 94478400 + 42393121 = 9720^2 + 6511^2 .

It is a cyclic number.

It is not a de Polignac number, because 136871521 - 2³ = 136871513 is a prime.

It is not a weakly prime, because it can be changed into another prime (136871591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68435760 + 68435761.

It is an arithmetic number, because the mean of its divisors is an integer number (68435761).

Almost surely, 2^136871521 is an apocalyptic number.

It is an amenable number.

136871521 is a deficient number, since it is larger than the sum of its proper divisors (1).

136871521 is an equidigital number, since it uses as much as digits as its factorization.

136871521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10080, while the sum is 34.

The square root of 136871521 is about 11699.2102724928. The cubic root of 136871521 is about 515.3524730696.

The spelling of 136871521 in words is "one hundred thirty-six million, eight hundred seventy-one thousand, five hundred twenty-one".