20917260 has 144 divisors (see below), whose sum is σ = 78152256. Its totient is φ = 4409856.

The previous prime is 20917243. The next prime is 20917277. The reversal of 20917260 is 6271902.

It is an interprime number because it is at equal distance from previous prime (20917243) and next prime (20917277).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 15742 + ... + 17018.

It is an arithmetic number, because the mean of its divisors is an integer number (542724).

Almost surely, 2^20917260 is an apocalyptic number.

20917260 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20917260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39076128).

20917260 is an abundant number, since it is smaller than the sum of its proper divisors (57234996).

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

20917260 is a wasteful number, since it uses less digits than its factorization.

20917260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1312 (or 1307 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 20917260 is about 4573.5391110168. The cubic root of 20917260 is about 275.5296020137.

The spelling of 20917260 in words is "twenty million, nine hundred seventeen thousand, two hundred sixty".