135579978 has 12 divisors (see below), whose sum is σ = 293756658. Its totient is φ = 45193320.

The previous prime is 135579911. The next prime is 135579979. The reversal of 135579978 is 879975531.

135579978 is a `hidden beast` number, since 13 + 557 + 9 + 9 + 78 = 666.

It can be written as a sum of positive squares in only one way, i.e., 120626289 + 14953689 = 10983^2 + 3867^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (135579979) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3766093 + ... + 3766128.

Almost surely, 2^135579978 is an apocalyptic number.

135579978 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

135579978 is an abundant number, since it is smaller than the sum of its proper divisors (158176680).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

135579978 is a wasteful number, since it uses less digits than its factorization.

135579978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7532229 (or 7532226 counting only the distinct ones).

The product of its digits is 2381400, while the sum is 54.

The square root of 135579978 is about 11643.8815693050. The cubic root of 135579978 is about 513.7263629525.

The spelling of 135579978 in words is "one hundred thirty-five million, five hundred seventy-nine thousand, nine hundred seventy-eight".