61631766 has 160 divisors (see below), whose sum is σ = 175633920. Its totient is φ = 15738624.

The previous prime is 61631747. The next prime is 61631819. The reversal of 61631766 is 66713616.

61631766 is a `hidden beast` number, since 616 + 31 + 7 + 6 + 6 = 666.

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

It is a self number, because there is not a number n which added to its sum of digits gives 61631766.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 443325 + ... + 443463.

It is an arithmetic number, because the mean of its divisors is an integer number (1097712).

Almost surely, 2^61631766 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61631766, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87816960).

61631766 is an abundant number, since it is smaller than the sum of its proper divisors (114002154).

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

61631766 is a wasteful number, since it uses less digits than its factorization.

61631766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200 (or 191 counting only the distinct ones).

The product of its digits is 27216, while the sum is 36.

The square root of 61631766 is about 7850.5901688981. The cubic root of 61631766 is about 395.0040399095.

The spelling of 61631766 in words is "sixty-one million, six hundred thirty-one thousand, seven hundred sixty-six".