61661136 has 40 divisors (see below), whose sum is σ = 161998560. Its totient is φ = 20204416.

The previous prime is 61661123. The next prime is 61661153. The reversal of 61661136 is 63116616.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8055 + ... + 13718.

It is an arithmetic number, because the mean of its divisors is an integer number (4049964).

Almost surely, 2^61661136 is an apocalyptic number.

It is an amenable number.

61661136 is an abundant number, since it is smaller than the sum of its proper divisors (100337424).

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

61661136 is a wasteful number, since it uses less digits than its factorization.

61661136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21843 (or 21837 counting only the distinct ones).

The product of its digits is 3888, while the sum is 30.

The square root of 61661136 is about 7852.4605061089. The cubic root of 61661136 is about 395.0667750166.

The spelling of 61661136 in words is "sixty-one million, six hundred sixty-one thousand, one hundred thirty-six".