17220981 has 4 divisors (see below), whose sum is σ = 22961312. Its totient is φ = 11480652.

The previous prime is 17220967. The next prime is 17220991. The reversal of 17220981 is 18902271.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 17220981 - 2¹⁷ = 17089909 is a prime.

It is a super-2 number, since 2×17220981² = 593124373204722, 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 (17220911) 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, 2870161 + ... + 2870166.

It is an arithmetic number, because the mean of its divisors is an integer number (5740328).

Almost surely, 2^17220981 is an apocalyptic number.

It is an amenable number.

17220981 is a deficient number, since it is larger than the sum of its proper divisors (5740331).

17220981 is an equidigital number, since it uses as much as digits as its factorization.

17220981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5740330.

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 17220981 is about 4149.8169839163. The cubic root of 17220981 is about 258.2374923931.

The spelling of 17220981 in words is "seventeen million, two hundred twenty thousand, nine hundred eighty-one".