61387709472 has 144 divisors (see below), whose sum is σ = 181284143040. Its totient is φ = 19681138176.

The previous prime is 61387709447. The next prime is 61387709479. The reversal of 61387709472 is 27490778316.

It is a tau number, because it is divible by the number of its divisors (144).

It is not an unprimeable number, because it can be changed into a prime (61387709479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2182603 + ... + 2210549.

It is an arithmetic number, because the mean of its divisors is an integer number (1258917660).

Almost surely, 2^61387709472 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 61387709472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90642071520).

61387709472 is an abundant number, since it is smaller than the sum of its proper divisors (119896433568).

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

61387709472 is a wasteful number, since it uses less digits than its factorization.

61387709472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28255 (or 28244 counting only the distinct ones).

The product of its (nonzero) digits is 3556224, while the sum is 54.

The spelling of 61387709472 in words is "sixty-one billion, three hundred eighty-seven million, seven hundred nine thousand, four hundred seventy-two".