136667381 has 8 divisors (see below), whose sum is σ = 140821464. Its totient is φ = 132537600.

The previous prime is 136667359. The next prime is 136667383. The reversal of 136667381 is 183766631.

It can be written as a sum of positive squares in 4 ways, for example, as 10666756 + 126000625 = 3266^2 + 11225^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-136667381 is a prime.

It is a super-2 number, since 2×136667381² = 37355946058798322, 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 (136667383) 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, 5681 + ... + 17481.

It is an arithmetic number, because the mean of its divisors is an integer number (17602683).

Almost surely, 2^136667381 is an apocalyptic number.

It is an amenable number.

136667381 is a deficient number, since it is larger than the sum of its proper divisors (4154083).

136667381 is a wasteful number, since it uses less digits than its factorization.

136667381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12151.

The product of its digits is 108864, while the sum is 41.

The square root of 136667381 is about 11690.4824964584. The cubic root of 136667381 is about 515.0961343771.

The spelling of 136667381 in words is "one hundred thirty-six million, six hundred sixty-seven thousand, three hundred eighty-one".