7791515820 has 768 divisors, whose sum is σ = 30656102400. Its totient is φ = 1617408000.

The previous prime is 7791515813. The next prime is 7791515863. The reversal of 7791515820 is 285151977.

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

It is an unprimeable number.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 59477155 + ... + 59477285.

It is an arithmetic number, because the mean of its divisors is an integer number (39916800).

Almost surely, 2^7791515820 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 7791515820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15328051200).

7791515820 is an abundant number, since it is smaller than the sum of its proper divisors (22864586580).

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

7791515820 is a wasteful number, since it uses less digits than its factorization.

7791515820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 227 (or 219 counting only the distinct ones).

The product of its (nonzero) digits is 176400, while the sum is 45.

The square root of 7791515820 is about 88269.5633839887. The cubic root of 7791515820 is about 1982.4731721580.

The spelling of 7791515820 in words is "seven billion, seven hundred ninety-one million, five hundred fifteen thousand, eight hundred twenty".