136838781 has 8 divisors (see below), whose sum is σ = 202724160. Its totient is φ = 91225836.

The previous prime is 136838777. The next prime is 136838783. The reversal of 136838781 is 187838631.

It is not a de Polignac number, because 136838781 - 2² = 136838777 is a prime.

It is a super-2 number, since 2×136838781² = 37449703971131922, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136838783) 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, 2534025 + ... + 2534078.

It is an arithmetic number, because the mean of its divisors is an integer number (25340520).

Almost surely, 2^136838781 is an apocalyptic number.

It is an amenable number.

136838781 is a deficient number, since it is larger than the sum of its proper divisors (65885379).

136838781 is an equidigital number, since it uses as much as digits as its factorization.

136838781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5068112 (or 5068106 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 136838781 is about 11697.8109490622. The cubic root of 136838781 is about 515.3113786053.

The spelling of 136838781 in words is "one hundred thirty-six million, eight hundred thirty-eight thousand, seven hundred eighty-one".