61188864 has 72 divisors (see below), whose sum is σ = 177680832. Its totient is φ = 18539520.

The previous prime is 61188863. The next prime is 61188887. The reversal of 61188864 is 46888116.

It is a super-2 number, since 2×61188864² = 7488154155220992, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (61188863) 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 7 ways as a sum of consecutive naturals, for example, 4827 + ... + 12069.

Almost surely, 2^61188864 is an apocalyptic number.

61188864 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 61188864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88840416).

61188864 is an abundant number, since it is smaller than the sum of its proper divisors (116491968).

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

61188864 is a wasteful number, since it uses less digits than its factorization.

61188864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7273 (or 7259 counting only the distinct ones).

The product of its digits is 73728, while the sum is 42.

The square root of 61188864 is about 7822.3311103532. The cubic root of 61188864 is about 394.0555634660.

The spelling of 61188864 in words is "sixty-one million, one hundred eighty-eight thousand, eight hundred sixty-four".