61591680 has 288 divisors, whose sum is σ = 232036740. Its totient is φ = 15040512.

The previous prime is 61591657. The next prime is 61591681. The reversal of 61591680 is 8619516.

61591680 is a `hidden beast` number, since 6 + 1 + 591 + 68 + 0 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 54997056 + 6594624 = 7416^2 + 2568^2 .

It is a tau number, because it is divible by the number of its divisors (288).

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 (61591681) 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 35 ways as a sum of consecutive naturals, for example, 1664622 + ... + 1664658.

Almost surely, 2^61591680 is an apocalyptic number.

61591680 is a gapful number since it is divisible by the number (60) 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 61591680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116018370).

61591680 is an abundant number, since it is smaller than the sum of its proper divisors (170445060).

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

61591680 is a wasteful number, since it uses less digits than its factorization.

61591680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 61591680 is about 7848.0366971619. The cubic root of 61591680 is about 394.9183829661.

The spelling of 61591680 in words is "sixty-one million, five hundred ninety-one thousand, six hundred eighty".