775980 has 60 divisors (see below), whose sum is σ = 2439360. Its totient is φ = 206496.

The previous prime is 775963. The next prime is 775987. The reversal of 775980 is 89577.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (775987) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1381 + ... + 1859.

It is an arithmetic number, because the mean of its divisors is an integer number (40656).

2⁷⁷⁵⁹⁸⁰ 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 775980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1219680).

775980 is an abundant number, since it is smaller than the sum of its proper divisors (1663380).

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

775980 is a wasteful number, since it uses less digits than its factorization.

775980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 500 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 36.

The square root of 775980 is about 880.8972698334. The cubic root of 775980 is about 91.8932283699.

The spelling of 775980 in words is "seven hundred seventy-five thousand, nine hundred eighty".