61604660 has 48 divisors (see below), whose sum is σ = 139951056. Its totient is φ = 22643712.

The previous prime is 61604659. The next prime is 61604663. The reversal of 61604660 is 6640616.

It can be written as a sum of positive squares in 8 ways, for example, as 17355556 + 44249104 = 4166^2 + 6652^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61604663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81002 + ... + 81758.

It is an arithmetic number, because the mean of its divisors is an integer number (2915647).

Almost surely, 2^61604660 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 61604660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69975528).

61604660 is an abundant number, since it is smaller than the sum of its proper divisors (78346396).

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

61604660 is a wasteful number, since it uses less digits than its factorization.

61604660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1092 (or 1090 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 61604660 is about 7848.8636120142. The cubic root of 61604660 is about 394.9461230795.

The spelling of 61604660 in words is "sixty-one million, six hundred four thousand, six hundred sixty".