77398251840 has 1344 divisors, whose sum is σ = 351419281920. Its totient is φ = 15931883520.

The previous prime is 77398251839. The next prime is 77398251851. The reversal of 77398251840 is 4815289377.

It is a happy number.

77398251840 is a `hidden beast` number, since 7 + 7 + 3 + 9 + 82 + 518 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a Harshad number since it is a multiple of its sum of digits (54).

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 191 ways as a sum of consecutive naturals, for example, 1887762220 + ... + 1887762260.

It is an arithmetic number, because the mean of its divisors is an integer number (261472680).

Almost surely, 2^77398251840 is an apocalyptic number.

77398251840 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 77398251840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175709640960).

77398251840 is an abundant number, since it is smaller than the sum of its proper divisors (274021030080).

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

77398251840 is an equidigital number, since it uses as much as digits as its factorization.

77398251840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 3386880, while the sum is 54.

The spelling of 77398251840 in words is "seventy-seven billion, three hundred ninety-eight million, two hundred fifty-one thousand, eight hundred forty".