21481159 has 6 divisors (see below), whose sum is σ = 24988344. Its totient is φ = 18412380.

The previous prime is 21481111. The next prime is 21481177. The reversal of 21481159 is 95118412.

It is a happy number.

It is not a de Polignac number, because 21481159 - 2⁹ = 21480647 is a prime.

It is a super-2 number, since 2×21481159² = 922880383966562, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21481159.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21481259) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 219147 + ... + 219244.

It is an arithmetic number, because the mean of its divisors is an integer number (4164724).

Almost surely, 2^21481159 is an apocalyptic number.

21481159 is a deficient number, since it is larger than the sum of its proper divisors (3507185).

21481159 is an equidigital number, since it uses as much as digits as its factorization.

21481159 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438405 (or 438398 counting only the distinct ones).

The product of its digits is 2880, while the sum is 31.

The square root of 21481159 is about 4634.7771251701. Note that the first 3 decimals coincide. The cubic root of 21481159 is about 277.9836394630.

The spelling of 21481159 in words is "twenty-one million, four hundred eighty-one thousand, one hundred fifty-nine".