61561044 has 72 divisors (see below), whose sum is σ = 161626920. Its totient is φ = 19740672.

The previous prime is 61561001. The next prime is 61561051. The reversal of 61561044 is 44016516.

61561044 is a `hidden beast` number, since 6 + 1 + 5 + 610 + 44 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 16160400 + 45400644 = 4020^2 + 6738^2 .

It is a junction number, because it is equal to n+sod(n) for n = 61560999 and 61561017.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 150312 + ... + 150720.

Almost surely, 2^61561044 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 61561044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80813460).

61561044 is an abundant number, since it is smaller than the sum of its proper divisors (100065876).

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

61561044 is a wasteful number, since it uses less digits than its factorization.

61561044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569 (or 564 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 61561044 is about 7846.0846286540. The cubic root of 61561044 is about 394.8528940011.

The spelling of 61561044 in words is "sixty-one million, five hundred sixty-one thousand, forty-four".