21022902 has 28 divisors (see below), whose sum is σ = 47283180. Its totient is φ = 7007148.

The previous prime is 21022901. The next prime is 21022909. The reversal of 21022902 is 20922012.

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 (21022901) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 5752 + ... + 8667.

It is an arithmetic number, because the mean of its divisors is an integer number (1688685).

Almost surely, 2^21022902 is an apocalyptic number.

21022902 is an abundant number, since it is smaller than the sum of its proper divisors (26260278).

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

21022902 is an equidigital number, since it uses as much as digits as its factorization.

21022902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14439 (or 14424 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 21022902 is about 4585.0738271046. The cubic root of 21022902 is about 275.9926746638.

Adding to 21022902 its reverse (20922012), we get a palindrome (41944914).

The spelling of 21022902 in words is "twenty-one million, twenty-two thousand, nine hundred two".