136781 has 8 divisors (see below), whose sum is σ = 150720. Its totient is φ = 123552.

The previous prime is 136777. The next prime is 136811. The reversal of 136781 is 187631.

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 136781 - 2² = 136777 is a prime.

It is a super-2 number, since 2×136781² = 37418083922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 136781.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 136781.

It is not an unprimeable number, because it can be changed into a prime (136711) 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, 281 + ... + 593.

It is an arithmetic number, because the mean of its divisors is an integer number (18840).

2¹³⁶⁷⁸¹ is an apocalyptic number.

It is an amenable number.

136781 is a deficient number, since it is larger than the sum of its proper divisors (13939).

136781 is a wasteful number, since it uses less digits than its factorization.

136781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355.

The product of its digits is 1008, while the sum is 26.

The square root of 136781 is about 369.8391542279. The cubic root of 136781 is about 51.5238837282.

The spelling of 136781 in words is "one hundred thirty-six thousand, seven hundred eighty-one".