61305984 has 144 divisors (see below), whose sum is σ = 185699670. Its totient is φ = 20155392.

The previous prime is 61305983. The next prime is 61305991. The reversal of 61305984 is 48950316.

61305984 is a `hidden beast` number, since 61 + 3 + 0 + 598 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 50808384 + 10497600 = 7128^2 + 3240^2 .

It is a tau number, because it is divible by the number of its divisors (144).

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

It is not an unprimeable number, because it can be changed into a prime (61305983) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 839772 + ... + 839844.

Almost surely, 2^61305984 is an apocalyptic number.

61305984 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61305984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92849835).

61305984 is an abundant number, since it is smaller than the sum of its proper divisors (124393686).

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

61305984 is an frugal number, since it uses more digits than its factorization.

61305984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111 (or 78 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 61305984 is about 7829.8137908893. The cubic root of 61305984 is about 394.3068203663.

The spelling of 61305984 in words is "sixty-one million, three hundred five thousand, nine hundred eighty-four".