61506564 has 72 divisors (see below), whose sum is σ = 172751040. Its totient is φ = 16962624.

The previous prime is 61506551. The next prime is 61506587. The reversal of 61506564 is 46560516.

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, 15249 + ... + 18855.

It is an arithmetic number, because the mean of its divisors is an integer number (2399320).

Almost surely, 2^61506564 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 61506564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86375520).

61506564 is an abundant number, since it is smaller than the sum of its proper divisors (111244476).

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

61506564 is a wasteful number, since it uses less digits than its factorization.

61506564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3657 (or 3648 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 33.

The square root of 61506564 is about 7842.6120648672. The cubic root of 61506564 is about 394.7363812785.

The spelling of 61506564 in words is "sixty-one million, five hundred six thousand, five hundred sixty-four".