77520281944 has 64 divisors (see below), whose sum is σ = 171851803200. Its totient is φ = 32091648000.

The previous prime is 77520281939. The next prime is 77520281977. The reversal of 77520281944 is 44918202577.

It is a super-2 number, since 2×77520281944² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64752 + ... + 399040.

It is an arithmetic number, because the mean of its divisors is an integer number (2685184425).

Almost surely, 2^77520281944 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 77520281944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85925901600).

77520281944 is an abundant number, since it is smaller than the sum of its proper divisors (94331521256).

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

77520281944 is a wasteful number, since it uses less digits than its factorization.

77520281944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334444 (or 334440 counting only the distinct ones).

The product of its (nonzero) digits is 1128960, while the sum is 49.

The spelling of 77520281944 in words is "seventy-seven billion, five hundred twenty million, two hundred eighty-one thousand, nine hundred forty-four".