61689379680 has 672 divisors, whose sum is σ = 236132384544. Its totient is φ = 15164817408.

The previous prime is 61689379673. The next prime is 61689379723. The reversal of 61689379680 is 8697398616.

61689379680 is a `hidden beast` number, since 616 + 8 + 9 + 3 + 7 + 9 + 6 + 8 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 105092347 + ... + 105092933.

It is an arithmetic number, because the mean of its divisors is an integer number (351387477).

Almost surely, 2^61689379680 is an apocalyptic number.

61689379680 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 61689379680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118066192272).

61689379680 is an abundant number, since it is smaller than the sum of its proper divisors (174443004864).

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

61689379680 is a wasteful number, since it uses less digits than its factorization.

61689379680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690 (or 667 counting only the distinct ones).

The product of its (nonzero) digits is 23514624, while the sum is 63.

The spelling of 61689379680 in words is "sixty-one billion, six hundred eighty-nine million, three hundred seventy-nine thousand, six hundred eighty".