21867273 has 24 divisors (see below), whose sum is σ = 33887840. Its totient is φ = 13935240.

The previous prime is 21867221. The next prime is 21867277. The reversal of 21867273 is 37276812.

It is not a de Polignac number, because 21867273 - 2¹⁰ = 21866249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21867277) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13518 + ... + 15048.

Almost surely, 2^21867273 is an apocalyptic number.

21867273 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21867273 is a deficient number, since it is larger than the sum of its proper divisors (12020567).

21867273 is a wasteful number, since it uses less digits than its factorization.

21867273 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1586 (or 1557 counting only the distinct ones).

The product of its digits is 28224, while the sum is 36.

The square root of 21867273 is about 4676.2456094606. The cubic root of 21867273 is about 279.6393017015.

The spelling of 21867273 in words is "twenty-one million, eight hundred sixty-seven thousand, two hundred seventy-three".