22404521 has 8 divisors (see below), whose sum is σ = 23764104. Its totient is φ = 21049600.

The previous prime is 22404497. The next prime is 22404523. The reversal of 22404521 is 12540422.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 912025 + 21492496 = 955^2 + 4636^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22404521 is a prime.

It is a super-2 number, since 2×22404521² = 1003925122478882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22404493 and 22404502.

It is not an unprimeable number, because it can be changed into a prime (22404523) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16571 + ... + 17871.

It is an arithmetic number, because the mean of its divisors is an integer number (2970513).

Almost surely, 2^22404521 is an apocalyptic number.

It is an amenable number.

22404521 is a deficient number, since it is larger than the sum of its proper divisors (1359583).

22404521 is a wasteful number, since it uses less digits than its factorization.

22404521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2331.

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

The square root of 22404521 is about 4733.3414201809. The cubic root of 22404521 is about 281.9109127911.

Adding to 22404521 its reverse (12540422), we get a palindrome (34944943).

The spelling of 22404521 in words is "twenty-two million, four hundred four thousand, five hundred twenty-one".