135660251 has 4 divisors (see below), whose sum is σ = 135884352. Its totient is φ = 135436152.

The previous prime is 135660211. The next prime is 135660269. The reversal of 135660251 is 152066531.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 135660251 - 2²⁶ = 68551387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (135660211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111140 + ... + 112353.

It is an arithmetic number, because the mean of its divisors is an integer number (33971088).

Almost surely, 2^135660251 is an apocalyptic number.

135660251 is a deficient number, since it is larger than the sum of its proper divisors (224101).

135660251 is an equidigital number, since it uses as much as digits as its factorization.

135660251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 224100.

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 135660251 is about 11647.3280626932. The cubic root of 135660251 is about 513.8277304773.

The spelling of 135660251 in words is "one hundred thirty-five million, six hundred sixty thousand, two hundred fifty-one".