21473171 has 2 divisors, whose sum is σ = 21473172. Its totient is φ = 21473170.

The previous prime is 21473147. The next prime is 21473201. The reversal of 21473171 is 17137412.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21473171 - 2⁶ = 21473107 is a prime.

It is a super-2 number, since 2×21473171² = 922194145590482, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21473171.

It is not a weakly prime, because it can be changed into another prime (21473071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10736585 + 10736586.

It is an arithmetic number, because the mean of its divisors is an integer number (10736586).

Almost surely, 2^21473171 is an apocalyptic number.

21473171 is a deficient number, since it is larger than the sum of its proper divisors (1).

21473171 is an equidigital number, since it uses as much as digits as its factorization.

21473171 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1176, while the sum is 26.

The square root of 21473171 is about 4633.9152991828. The cubic root of 21473171 is about 277.9491781224.

The spelling of 21473171 in words is "twenty-one million, four hundred seventy-three thousand, one hundred seventy-one".