77315523840 has 576 divisors, whose sum is σ = 282385958400. Its totient is φ = 20274831360.

The previous prime is 77315523829. The next prime is 77315523841. The reversal of 77315523840 is 4832551377.

77315523840 is a `hidden beast` number, since 7 + 73 + 15 + 523 + 8 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77315523841) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 198754366 + ... + 198754754.

It is an arithmetic number, because the mean of its divisors is an integer number (490253400).

Almost surely, 2^77315523840 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 77315523840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141192979200).

77315523840 is an abundant number, since it is smaller than the sum of its proper divisors (205070434560).

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

77315523840 is an frugal number, since it uses more digits than its factorization.

77315523840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 502 (or 470 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 45.

The spelling of 77315523840 in words is "seventy-seven billion, three hundred fifteen million, five hundred twenty-three thousand, eight hundred forty".