135527721 has 16 divisors (see below), whose sum is σ = 208650624. Its totient is φ = 76644864.

The previous prime is 135527699. The next prime is 135527729. The reversal of 135527721 is 127725531.

It is a happy number.

135527721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 135527721 - 2⁷ = 135527593 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (135527729) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31230 + ... + 35303.

It is an arithmetic number, because the mean of its divisors is an integer number (13040664).

Almost surely, 2^135527721 is an apocalyptic number.

It is an amenable number.

135527721 is a deficient number, since it is larger than the sum of its proper divisors (73122903).

135527721 is an equidigital number, since it uses as much as digits as its factorization.

135527721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66640.

The product of its digits is 14700, while the sum is 33.

The square root of 135527721 is about 11641.6373848355. The cubic root of 135527721 is about 513.6603521035.

The spelling of 135527721 in words is "one hundred thirty-five million, five hundred twenty-seven thousand, seven hundred twenty-one".