61516442880 has 432 divisors, whose sum is σ = 225908766720. Its totient is φ = 15411658752.

The previous prime is 61516442857. The next prime is 61516442881. The reversal of 61516442880 is 8824461516.

It is a happy number.

61516442880 is a `hidden beast` number, since 61 + 5 + 164 + 428 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61516442881) 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, 27796654 + ... + 27798866.

It is an arithmetic number, because the mean of its divisors is an integer number (522936960).

Almost surely, 2^61516442880 is an apocalyptic number.

61516442880 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 61516442880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112954383360).

61516442880 is an abundant number, since it is smaller than the sum of its proper divisors (164392323840).

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

61516442880 is a wasteful number, since it uses less digits than its factorization.

61516442880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2386 (or 2369 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The spelling of 61516442880 in words is "sixty-one billion, five hundred sixteen million, four hundred forty-two thousand, eight hundred eighty".