135297981 has 72 divisors (see below), whose sum is σ = 251736576. Its totient is φ = 68117760.

The previous prime is 135297977. The next prime is 135298001. The reversal of 135297981 is 189792531.

135297981 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 135297981 - 2² = 135297977 is a prime.

It is a super-2 number, since 2×135297981² = 36611087325352722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135297931) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1853361 + ... + 1853433.

Almost surely, 2^135297981 is an apocalyptic number.

It is an amenable number.

135297981 is a deficient number, since it is larger than the sum of its proper divisors (116438595).

135297981 is a wasteful number, since it uses less digits than its factorization.

135297981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203 (or 127 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The square root of 135297981 is about 11631.7660310032. The cubic root of 135297981 is about 513.3699439322.

It can be divided in two parts, 135 and 297981, that added together give a square (298116 = 546²).

The spelling of 135297981 in words is "one hundred thirty-five million, two hundred ninety-seven thousand, nine hundred eighty-one".