136656263521 has 4 divisors (see below), whose sum is σ = 141368548500. Its totient is φ = 131943978544.

The previous prime is 136656263509. The next prime is 136656263533. The reversal of 136656263521 is 125362656631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 125362656631 = 74377 ⋅1685503.

It is an interprime number because it is at equal distance from previous prime (136656263509) and next prime (136656263533).

It can be written as a sum of positive squares in 2 ways, for example, as 59087886400 + 77568377121 = 243080^2 + 278511^2 .

It is a cyclic number.

It is not a de Polignac number, because 136656263521 - 2¹⁷ = 136656132449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (136656263921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2356142446 + ... + 2356142503.

It is an arithmetic number, because the mean of its divisors is an integer number (35342137125).

Almost surely, 2^136656263521 is an apocalyptic number.

It is an amenable number.

136656263521 is a deficient number, since it is larger than the sum of its proper divisors (4712284979).

136656263521 is an equidigital number, since it uses as much as digits as its factorization.

136656263521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4712284978.

The product of its digits is 1166400, while the sum is 46.

The spelling of 136656263521 in words is "one hundred thirty-six billion, six hundred fifty-six million, two hundred sixty-three thousand, five hundred twenty-one".