22006404 has 120 divisors (see below), whose sum is σ = 68085248. Its totient is φ = 6065280.

The previous prime is 22006349. The next prime is 22006409. The reversal of 22006404 is 40460022.

22006404 is a `hidden beast` number, since 2 + 20 + 0 + 640 + 4 = 666.

It is a super-2 number, since 2×22006404² = 968563634022432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22006409) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 70152 + ... + 70464.

Almost surely, 2^22006404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22006404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34042624).

22006404 is an abundant number, since it is smaller than the sum of its proper divisors (46078844).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

22006404 is a wasteful number, since it uses less digits than its factorization.

22006404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 367 (or 356 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 22006404 is about 4691.0983788448. The cubic root of 22006404 is about 280.2311187004.

Adding to 22006404 its reverse (40460022), we get a palindrome (62466426).

The spelling of 22006404 in words is "twenty-two million, six thousand, four hundred four".