136781407 has 4 divisors (see below), whose sum is σ = 156321616. Its totient is φ = 117241200.

The previous prime is 136781401. The next prime is 136781419. The reversal of 136781407 is 704187631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 704187631 = 7 ⋅100598233.

It is a cyclic number.

It is not a de Polignac number, because 136781407 - 2⁷ = 136781279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136781401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9770094 + ... + 9770107.

It is an arithmetic number, because the mean of its divisors is an integer number (39080404).

Almost surely, 2^136781407 is an apocalyptic number.

136781407 is a deficient number, since it is larger than the sum of its proper divisors (19540209).

136781407 is an equidigital number, since it uses as much as digits as its factorization.

136781407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19540208.

The product of its (nonzero) digits is 28224, while the sum is 37.

The square root of 136781407 is about 11695.3583527825. The cubic root of 136781407 is about 515.2393483230.

The spelling of 136781407 in words is "one hundred thirty-six million, seven hundred eighty-one thousand, four hundred seven".