135681556 has 12 divisors (see below), whose sum is σ = 251410068. Its totient is φ = 63850112.

The previous prime is 135681541. The next prime is 135681569. The reversal of 135681556 is 655186531.

It can be written as a sum of positive squares in 2 ways, for example, as 42250000 + 93431556 = 6500^2 + 9666^2 .

It is a super-2 number, since 2×135681556² = 36818969277162272, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 997591 + ... + 997726.

It is an arithmetic number, because the mean of its divisors is an integer number (20950839).

Almost surely, 2^135681556 is an apocalyptic number.

It is an amenable number.

135681556 is a deficient number, since it is larger than the sum of its proper divisors (115728512).

135681556 is a wasteful number, since it uses less digits than its factorization.

135681556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1995338 (or 1995336 counting only the distinct ones).

The product of its digits is 108000, while the sum is 40.

The square root of 135681556 is about 11648.2426142316. The cubic root of 135681556 is about 513.8546273924.

The spelling of 135681556 in words is "one hundred thirty-five million, six hundred eighty-one thousand, five hundred fifty-six".