61386312064 has 128 divisors (see below), whose sum is σ = 153272217600. Its totient is φ = 23790796800.

The previous prime is 61386312041. The next prime is 61386312067. The reversal of 61386312064 is 46021368316.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61386312067) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1866192 + ... + 1898800.

It is an arithmetic number, because the mean of its divisors is an integer number (1197439200).

Almost surely, 2^61386312064 is an apocalyptic number.

61386312064 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 61386312064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76636108800).

61386312064 is an abundant number, since it is smaller than the sum of its proper divisors (91885905536).

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

61386312064 is a wasteful number, since it uses less digits than its factorization.

61386312064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32832 (or 32820 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 40.

The spelling of 61386312064 in words is "sixty-one billion, three hundred eighty-six million, three hundred twelve thousand, sixty-four".