61801947648 has 400 divisors, whose sum is σ = 211758053760. Its totient is φ = 17578819584.

The previous prime is 61801947629. The next prime is 61801947661. The reversal of 61801947648 is 84674910816.

61801947648 is a `hidden beast` number, since 618 + 0 + 19 + 4 + 7 + 6 + 4 + 8 = 666.

It is a super-2 number, since 2×61801947648² (a number of 22 digits) contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 61801947594 and 61801947603.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 104218840 + ... + 104219432.

Almost surely, 2^61801947648 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61801947648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105879026880).

61801947648 is an abundant number, since it is smaller than the sum of its proper divisors (149956106112).

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

61801947648 is an equidigital number, since it uses as much as digits as its factorization.

61801947648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989 (or 964 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 54.

The spelling of 61801947648 in words is "sixty-one billion, eight hundred one million, nine hundred forty-seven thousand, six hundred forty-eight".