21422456 has 16 divisors (see below), whose sum is σ = 43818840. Its totient is φ = 9737440.

The previous prime is 21422449. The next prime is 21422461. The reversal of 21422456 is 65422412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121631 + ... + 121806.

Almost surely, 2^21422456 is an apocalyptic number.

It is an amenable number.

21422456 is an abundant number, since it is smaller than the sum of its proper divisors (22396384).

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

21422456 is a wasteful number, since it uses less digits than its factorization.

21422456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243454 (or 243450 counting only the distinct ones).

The product of its digits is 3840, while the sum is 26.

The square root of 21422456 is about 4628.4399099481. The cubic root of 21422456 is about 277.7301869521.

Adding to 21422456 its reverse (65422412), we get a palindrome (86844868).

The spelling of 21422456 in words is "twenty-one million, four hundred twenty-two thousand, four hundred fifty-six".