61309554011440 has 320 divisors, whose sum is σ = 167454907628544. Its totient is φ = 20443214905344.

The previous prime is 61309554011417. The next prime is 61309554011441. The reversal of 61309554011440 is 4411045590316.

It is a super-2 number, since 2×61309554011440² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61309554011441) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1089590187 + ... + 1089646453.

Almost surely, 2^{61309554011440} 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 61309554011440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83727453814272).

61309554011440 is an abundant number, since it is smaller than the sum of its proper divisors (106145353617104).

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

61309554011440 is a wasteful number, since it uses less digits than its factorization.

61309554011440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56724 (or 56718 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 43.

The spelling of 61309554011440 in words is "sixty-one trillion, three hundred nine billion, five hundred fifty-four million, eleven thousand, four hundred forty".