917980 has 48 divisors (see below), whose sum is σ = 2257920. Its totient is φ = 307008.

The previous prime is 917971. The next prime is 917993. The reversal of 917980 is 89719.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11019 + ... + 11101.

It is an arithmetic number, because the mean of its divisors is an integer number (47040).

2⁹¹⁷⁹⁸⁰ 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 917980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1128960).

917980 is an abundant number, since it is smaller than the sum of its proper divisors (1339940).

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

917980 is a wasteful number, since it uses less digits than its factorization.

917980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178 (or 176 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 34.

The square root of 917980 is about 958.1127282319. The cubic root of 917980 is about 97.1876482354.

The spelling of 917980 in words is "nine hundred seventeen thousand, nine hundred eighty".