77391444049920 has 3840 divisors, whose sum is σ = 375940813248000. Its totient is φ = 14205604331520.

The previous prime is 77391444049877. The next prime is 77391444049921. The reversal of 77391444049920 is 2994044419377.

77391444049920 is a `hidden beast` number, since 7 + 73 + 9 + 14 + 4 + 40 + 499 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (3840).

It is a super-2 number, since 2×77391444049920² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (77391444049921) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 684880035784 + ... + 684880035896.

It is an arithmetic number, because the mean of its divisors is an integer number (97901253450).

Almost surely, 2^{77391444049920} is an apocalyptic number.

77391444049920 is a gapful number since it is divisible by the number (70) 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 77391444049920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187970406624000).

77391444049920 is an abundant number, since it is smaller than the sum of its proper divisors (298549369198080).

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

77391444049920 is a wasteful number, since it uses less digits than its factorization.

77391444049920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222 (or 183 counting only the distinct ones).

The product of its (nonzero) digits is 54867456, while the sum is 63.

The spelling of 77391444049920 in words is "seventy-seven trillion, three hundred ninety-one billion, four hundred forty-four million, forty-nine thousand, nine hundred twenty".