21440522 has 4 divisors (see below), whose sum is σ = 32160786. Its totient is φ = 10720260.

The previous prime is 21440491. The next prime is 21440527. The reversal of 21440522 is 22504412.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 14145121 + 7295401 = 3761^2 + 2701^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21440494 and 21440503.

It is not an unprimeable number, because it can be changed into a prime (21440527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5360129 + ... + 5360132.

Almost surely, 2^21440522 is an apocalyptic number.

21440522 is a deficient number, since it is larger than the sum of its proper divisors (10720264).

21440522 is a wasteful number, since it uses less digits than its factorization.

21440522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10720263.

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 21440522 is about 4630.3911281878. The cubic root of 21440522 is about 277.8082368851.

Adding to 21440522 its reverse (22504412), we get a palindrome (43944934).

The spelling of 21440522 in words is "twenty-one million, four hundred forty thousand, five hundred twenty-two".