61641936 has 90 divisors (see below), whose sum is σ = 179016630. Its totient is φ = 19799808.

The previous prime is 61641929. The next prime is 61641941. The reversal of 61641936 is 63914616.

61641936 is a `hidden beast` number, since 6 + 1 + 641 + 9 + 3 + 6 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 18870336 + 42771600 = 4344^2 + 6540^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

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 61641936.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 120850 + ... + 121358.

Almost surely, 2^61641936 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61641936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89508315).

61641936 is an abundant number, since it is smaller than the sum of its proper divisors (117374694).

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

61641936 is a wasteful number, since it uses less digits than its factorization.

61641936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 581 (or 543 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 61641936 is about 7851.2378641842. The cubic root of 61641936 is about 395.0257655575.

It can be divided in two parts, 6164 and 1936, that added together give a square (8100 = 90²).

The spelling of 61641936 in words is "sixty-one million, six hundred forty-one thousand, nine hundred thirty-six".