17420981 has 4 divisors (see below), whose sum is σ = 17434572. Its totient is φ = 17407392.

The previous prime is 17420957. The next prime is 17420987. The reversal of 17420981 is 18902471.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6916900 + 10504081 = 2630^2 + 3241^2 .

It is a cyclic number.

It is not a de Polignac number, because 17420981 - 2⁶ = 17420917 is a prime.

It is a super-2 number, since 2×17420981² = 606981158004722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17420987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4646 + ... + 7511.

It is an arithmetic number, because the mean of its divisors is an integer number (4358643).

Almost surely, 2^17420981 is an apocalyptic number.

It is an amenable number.

17420981 is a deficient number, since it is larger than the sum of its proper divisors (13591).

17420981 is a wasteful number, since it uses less digits than its factorization.

17420981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13590.

The product of its (nonzero) digits is 4032, while the sum is 32.

The square root of 17420981 is about 4173.8448701407. The cubic root of 17420981 is about 259.2333481343.

The spelling of 17420981 in words is "seventeen million, four hundred twenty thousand, nine hundred eighty-one".