61391880 has 192 divisors, whose sum is σ = 224078400. Its totient is φ = 14446080.

The previous prime is 61391857. The next prime is 61391881. The reversal of 61391880 is 8819316.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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 (61391881) 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, 146311 + ... + 146729.

It is an arithmetic number, because the mean of its divisors is an integer number (1167075).

Almost surely, 2^61391880 is an apocalyptic number.

61391880 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 61391880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112039200).

61391880 is an abundant number, since it is smaller than the sum of its proper divisors (162686520).

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

61391880 is a wasteful number, since it uses less digits than its factorization.

61391880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484 (or 477 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 61391880 is about 7835.2970588230. The cubic root of 61391880 is about 394.4908892536.

The spelling of 61391880 in words is "sixty-one million, three hundred ninety-one thousand, eight hundred eighty".