135124991 has 4 divisors (see below), whose sum is σ = 135182232. Its totient is φ = 135067752.

The previous prime is 135124973. The next prime is 135125021. The reversal of 135124991 is 199421531.

It is a happy number.

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 135124991 - 2²² = 130930687 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 (135124901) 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, 24920 + ... + 29853.

It is an arithmetic number, because the mean of its divisors is an integer number (33795558).

Almost surely, 2^135124991 is an apocalyptic number.

135124991 is a deficient number, since it is larger than the sum of its proper divisors (57241).

135124991 is an equidigital number, since it uses as much as digits as its factorization.

135124991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57240.

The product of its digits is 9720, while the sum is 35.

The square root of 135124991 is about 11624.3275504435. The cubic root of 135124991 is about 513.1510548739.

The spelling of 135124991 in words is "one hundred thirty-five million, one hundred twenty-four thousand, nine hundred ninety-one".