21422502 has 16 divisors (see below), whose sum is σ = 47605680. Its totient is φ = 7140816.

The previous prime is 21422501. The next prime is 21422537. The reversal of 21422502 is 20522412.

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 (21422501) 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, 198303 + ... + 198410.

It is an arithmetic number, because the mean of its divisors is an integer number (2975355).

Almost surely, 2^21422502 is an apocalyptic number.

21422502 is an abundant number, since it is smaller than the sum of its proper divisors (26183178).

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

21422502 is a wasteful number, since it uses less digits than its factorization.

21422502 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396724 (or 396718 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 21422502 is about 4628.4448792224. Note that the first 3 decimals coincide. The cubic root of 21422502 is about 277.7303857400.

Adding to 21422502 its reverse (20522412), we get a palindrome (41944914).

The spelling of 21422502 in words is "twenty-one million, four hundred twenty-two thousand, five hundred two".