61744573440 has 528 divisors, whose sum is σ = 235030906656. Its totient is φ = 14863564800.

The previous prime is 61744573439. The next prime is 61744573447. The reversal of 61744573440 is 4437544716.

61744573440 is a `hidden beast` number, since 6 + 1 + 74 + 4 + 573 + 4 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (528).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (61744573447) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 91744944 + ... + 91745616.

Almost surely, 2^61744573440 is an apocalyptic number.

61744573440 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 61744573440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117515453328).

61744573440 is an abundant number, since it is smaller than the sum of its proper divisors (173286333216).

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

61744573440 is a wasteful number, since it uses less digits than its factorization.

61744573440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 896 (or 875 counting only the distinct ones).

The product of its (nonzero) digits is 1128960, while the sum is 45.

The spelling of 61744573440 in words is "sixty-one billion, seven hundred forty-four million, five hundred seventy-three thousand, four hundred forty".