61920144 has 240 divisors, whose sum is σ = 212319744. Its totient is φ = 16588800.

The previous prime is 61920143. The next prime is 61920161. The reversal of 61920144 is 44102916.

61920144 is a `hidden beast` number, since 619 + 2 + 0 + 1 + 44 = 666.

It is not an unprimeable number, because it can be changed into a prime (61920143) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 638304 + ... + 638400.

Almost surely, 2^61920144 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 61920144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106159872).

61920144 is an abundant number, since it is smaller than the sum of its proper divisors (150399600).

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

61920144 is a wasteful number, since it uses less digits than its factorization.

61920144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166 (or 157 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 61920144 is about 7868.9353790713. The cubic root of 61920144 is about 395.6191624813.

The spelling of 61920144 in words is "sixty-one million, nine hundred twenty thousand, one hundred forty-four".