16621233 has 4 divisors (see below), whose sum is σ = 22161648. Its totient is φ = 11080820.

The previous prime is 16621229. The next prime is 16621259. The reversal of 16621233 is 33212661.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 33212661 = 3 ⋅11070887.

It is a cyclic number.

It is not a de Polignac number, because 16621233 - 2² = 16621229 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16621133) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2770203 + ... + 2770208.

It is an arithmetic number, because the mean of its divisors is an integer number (5540412).

Almost surely, 2^16621233 is an apocalyptic number.

It is an amenable number.

16621233 is a deficient number, since it is larger than the sum of its proper divisors (5540415).

16621233 is an equidigital number, since it uses as much as digits as its factorization.

16621233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5540414.

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

The square root of 16621233 is about 4076.9146422264. The cubic root of 16621233 is about 255.2041579185.

Adding to 16621233 its reverse (33212661), we get a palindrome (49833894).

The spelling of 16621233 in words is "sixteen million, six hundred twenty-one thousand, two hundred thirty-three".