136525781 has 4 divisors (see below), whose sum is σ = 156029472. Its totient is φ = 117022092.

The previous prime is 136525771. The next prime is 136525789. The reversal of 136525781 is 187525631.

136525781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 187525631 = 281 ⋅667351.

It is a cyclic number.

It is not a de Polignac number, because 136525781 - 2⁶ = 136525717 is a prime.

It is a super-2 number, since 2×136525781² = 37278577755319922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (136525789) 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, 9751835 + ... + 9751848.

It is an arithmetic number, because the mean of its divisors is an integer number (39007368).

Almost surely, 2^136525781 is an apocalyptic number.

It is an amenable number.

136525781 is a deficient number, since it is larger than the sum of its proper divisors (19503691).

136525781 is an equidigital number, since it uses as much as digits as its factorization.

136525781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19503690.

The product of its digits is 50400, while the sum is 38.

The square root of 136525781 is about 11684.4247184018. The cubic root of 136525781 is about 514.9181772166.

The spelling of 136525781 in words is "one hundred thirty-six million, five hundred twenty-five thousand, seven hundred eighty-one".