136613581 has 8 divisors (see below), whose sum is σ = 155776824. Its totient is φ = 118686720.

The previous prime is 136613569. The next prime is 136613593. The reversal of 136613581 is 185316631.

It is an interprime number because it is at equal distance from previous prime (136613569) and next prime (136613593).

It can be written as a sum of positive squares in 4 ways, for example, as 54257956 + 82355625 = 7366^2 + 9075^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 136613581 - 2⁵ = 136613549 is a prime.

It is a super-2 number, since 2×136613581² = 37326541027287122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136610581) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 308860 + ... + 309301.

It is an arithmetic number, because the mean of its divisors is an integer number (19472103).

Almost surely, 2^136613581 is an apocalyptic number.

It is an amenable number.

136613581 is a deficient number, since it is larger than the sum of its proper divisors (19163243).

136613581 is a wasteful number, since it uses less digits than its factorization.

136613581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 618191.

The product of its digits is 12960, while the sum is 34.

The square root of 136613581 is about 11688.1812528725. The cubic root of 136613581 is about 515.0285351958.

The spelling of 136613581 in words is "one hundred thirty-six million, six hundred thirteen thousand, five hundred eighty-one".