21227499 has 24 divisors (see below), whose sum is σ = 31401552. Its totient is φ = 13815360.

The previous prime is 21227477. The next prime is 21227501. The reversal of 21227499 is 99472212.

It is not a de Polignac number, because 21227499 - 2⁸ = 21227243 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21227419) 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, 117189 + ... + 117369.

It is an arithmetic number, because the mean of its divisors is an integer number (1308398).

Almost surely, 2^21227499 is an apocalyptic number.

21227499 is a deficient number, since it is larger than the sum of its proper divisors (10174053).

21227499 is a wasteful number, since it uses less digits than its factorization.

21227499 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427 (or 424 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 21227499 is about 4607.3310061249. The cubic root of 21227499 is about 276.8851152913.

The spelling of 21227499 in words is "twenty-one million, two hundred twenty-seven thousand, four hundred ninety-nine".