775880820 has 288 divisors, whose sum is σ = 2833294464. Its totient is φ = 169344000.

The previous prime is 775880801. The next prime is 775880821. The reversal of 775880820 is 28088577.

It is a happy number.

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 (775880821) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1106470 + ... + 1107170.

It is an arithmetic number, because the mean of its divisors is an integer number (9837828).

Almost surely, 2^775880820 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 775880820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1416647232).

775880820 is an abundant number, since it is smaller than the sum of its proper divisors (2057413644).

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

775880820 is a wasteful number, since it uses less digits than its factorization.

775880820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 783 (or 778 counting only the distinct ones).

The product of its (nonzero) digits is 250880, while the sum is 45.

The square root of 775880820 is about 27854.6373158941. The cubic root of 775880820 is about 918.8931316640.

The spelling of 775880820 in words is "seven hundred seventy-five million, eight hundred eighty thousand, eight hundred twenty".