61639418880 has 1056 divisors, whose sum is σ = 247352012544. Its totient is φ = 14619377664.

The previous prime is 61639418837. The next prime is 61639418899. The reversal of 61639418880 is 8881493616.

61639418880 is a `hidden beast` number, since 616 + 3 + 9 + 4 + 18 + 8 + 8 + 0 = 666.

61639418880 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 598440909 + ... + 598441011.

Almost surely, 2^61639418880 is an apocalyptic number.

61639418880 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 61639418880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123676006272).

61639418880 is an abundant number, since it is smaller than the sum of its proper divisors (185712593664).

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

61639418880 is a wasteful number, since it uses less digits than its factorization.

61639418880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193 (or 163 counting only the distinct ones).

The product of its (nonzero) digits is 1990656, while the sum is 54.

The spelling of 61639418880 in words is "sixty-one billion, six hundred thirty-nine million, four hundred eighteen thousand, eight hundred eighty".