61991441338464 has 192 divisors, whose sum is σ = 203608254044160. Its totient is φ = 18179308224000.

The previous prime is 61991441338451. The next prime is 61991441338493. The reversal of 61991441338464 is 46483314419916.

It is a happy number.

61991441338464 is a `hidden beast` number, since 6 + 1 + 9 + 91 + 44 + 13 + 38 + 464 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 104909707 + ... + 105498954.

It is an arithmetic number, because the mean of its divisors is an integer number (1060459656480).

Almost surely, 2^{61991441338464} is an apocalyptic number.

It is an amenable number.

61991441338464 is an abundant number, since it is smaller than the sum of its proper divisors (141616812705696).

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

61991441338464 is a wasteful number, since it uses less digits than its factorization.

61991441338464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210408722 (or 210408708 counting only the distinct ones).

The product of its digits is 53747712, while the sum is 63.

The spelling of 61991441338464 in words is "sixty-one trillion, nine hundred ninety-one billion, four hundred forty-one million, three hundred thirty-eight thousand, four hundred sixty-four".