61005947904 has 352 divisors, whose sum is σ = 203920502400. Its totient is φ = 17846599680.

The previous prime is 61005947867. The next prime is 61005947917. The reversal of 61005947904 is 40974950016.

It is a tau number, because it is divible by the number of its divisors (352).

It is a self number, because there is not a number n which added to its sum of digits gives 61005947904.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8816254 + ... + 8823170.

Almost surely, 2^61005947904 is an apocalyptic number.

61005947904 is a gapful number since it is divisible by the number (64) 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 61005947904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101960251200).

61005947904 is an abundant number, since it is smaller than the sum of its proper divisors (142914554496).

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

61005947904 is a wasteful number, since it uses less digits than its factorization.

61005947904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6986 (or 6962 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 45.

The spelling of 61005947904 in words is "sixty-one billion, five million, nine hundred forty-seven thousand, nine hundred four".