21340422 has 20 divisors (see below), whose sum is σ = 47818716. Its totient is φ = 7113420.

The previous prime is 21340421. The next prime is 21340441. The reversal of 21340422 is 22404312.

It is a super-2 number, since 2×21340422² = 910827222276168, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 21340395 and 21340404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21340421) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 65704 + ... + 66027.

Almost surely, 2^21340422 is an apocalyptic number.

21340422 is an abundant number, since it is smaller than the sum of its proper divisors (26478294).

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

21340422 is a wasteful number, since it uses less digits than its factorization.

21340422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131745 (or 131736 counting only the distinct ones).

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

The square root of 21340422 is about 4619.5694604584. The cubic root of 21340422 is about 277.3752251319.

Adding to 21340422 its reverse (22404312), we get a palindrome (43744734).

The spelling of 21340422 in words is "twenty-one million, three hundred forty thousand, four hundred twenty-two".