21166233 has 32 divisors (see below), whose sum is σ = 32624640. Its totient is φ = 12080640.

The previous prime is 21166217. The next prime is 21166253. The reversal of 21166233 is 33266112.

It is a happy number.

It is not a de Polignac number, because 21166233 - 2⁴ = 21166217 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21166253) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 59785 + ... + 60137.

It is an arithmetic number, because the mean of its divisors is an integer number (1019520).

Almost surely, 2^21166233 is an apocalyptic number.

21166233 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21166233 is a deficient number, since it is larger than the sum of its proper divisors (11458407).

21166233 is a wasteful number, since it uses less digits than its factorization.

21166233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469.

The product of its digits is 1296, while the sum is 24.

The square root of 21166233 is about 4600.6774501154. The cubic root of 21166233 is about 276.6184801807.

The spelling of 21166233 in words is "twenty-one million, one hundred sixty-six thousand, two hundred thirty-three".