21626222 has 4 divisors (see below), whose sum is σ = 32439336. Its totient is φ = 10813110.

The previous prime is 21626219. The next prime is 21626281. The reversal of 21626222 is 22262612.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5406554 + ... + 5406557.

It is an arithmetic number, because the mean of its divisors is an integer number (8109834).

Almost surely, 2^21626222 is an apocalyptic number.

21626222 is a deficient number, since it is larger than the sum of its proper divisors (10813114).

21626222 is a wasteful number, since it uses less digits than its factorization.

21626222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10813113.

The product of its digits is 1152, while the sum is 23.

The square root of 21626222 is about 4650.4001978324. The cubic root of 21626222 is about 278.6079805016.

Adding to 21626222 its reverse (22262612), we get a palindrome (43888834).

The spelling of 21626222 in words is "twenty-one million, six hundred twenty-six thousand, two hundred twenty-two".