136581381 has 12 divisors (see below), whose sum is σ = 203648640. Its totient is φ = 88116840.

The previous prime is 136581377. The next prime is 136581407. The reversal of 136581381 is 183185631.

It is not a de Polignac number, because 136581381 - 2² = 136581377 is a prime.

It is a super-2 number, since 2×136581381² = 37308947271734322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136581301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 244491 + ... + 245048.

It is an arithmetic number, because the mean of its divisors is an integer number (16970720).

Almost surely, 2^136581381 is an apocalyptic number.

It is an amenable number.

136581381 is a deficient number, since it is larger than the sum of its proper divisors (67067259).

136581381 is a wasteful number, since it uses less digits than its factorization.

136581381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 489576 (or 489573 counting only the distinct ones).

The product of its digits is 17280, while the sum is 36.

The square root of 136581381 is about 11686.8037118795. The cubic root of 136581381 is about 514.9880677161.

The spelling of 136581381 in words is "one hundred thirty-six million, five hundred eighty-one thousand, three hundred eighty-one".