13221998 has 4 divisors (see below), whose sum is σ = 19833000. Its totient is φ = 6610998.

The previous prime is 13221997. The next prime is 13222031. The reversal of 13221998 is 89912231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 89912231 = 61 ⋅1473971.

It is a super-2 number, since 2×13221998² = 349642462224008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13221997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3305498 + ... + 3305501.

It is an arithmetic number, because the mean of its divisors is an integer number (4958250).

Almost surely, 2^13221998 is an apocalyptic number.

13221998 is a deficient number, since it is larger than the sum of its proper divisors (6611002).

13221998 is an equidigital number, since it uses as much as digits as its factorization.

13221998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6611001.

The product of its digits is 7776, while the sum is 35.

The square root of 13221998 is about 3636.2065397884. The cubic root of 13221998 is about 236.4643614904.

The spelling of 13221998 in words is "thirteen million, two hundred twenty-one thousand, nine hundred ninety-eight".