21202902 has 24 divisors (see below), whose sum is σ = 52502736. Its totient is φ = 6057936.

The previous prime is 21202901. The next prime is 21202919. The reversal of 21202902 is 20920212.

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 (21202901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 84013 + ... + 84264.

It is an arithmetic number, because the mean of its divisors is an integer number (2187614).

Almost surely, 2^21202902 is an apocalyptic number.

21202902 is an abundant number, since it is smaller than the sum of its proper divisors (31299834).

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

21202902 is a wasteful number, since it uses less digits than its factorization.

21202902 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168292 (or 168289 counting only the distinct ones).

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

The square root of 21202902 is about 4604.6608995669. The cubic root of 21202902 is about 276.7781286666.

The spelling of 21202902 in words is "twenty-one million, two hundred two thousand, nine hundred two".