21202402 has 24 divisors (see below), whose sum is σ = 34751700. Its totient is φ = 9696960.

The previous prime is 21202399. The next prime is 21202403. The reversal of 21202402 is 20420212.

It can be written as a sum of positive squares in 6 ways, for example, as 690561 + 20511841 = 831^2 + 4529^2 .

It is a Harshad number since it is a multiple of its sum of digits (13).

It is not an unprimeable number, because it can be changed into a prime (21202403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50152 + ... + 50572.

Almost surely, 2^21202402 is an apocalyptic number.

21202402 is a deficient number, since it is larger than the sum of its proper divisors (13549298).

21202402 is a wasteful number, since it uses less digits than its factorization.

21202402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 598 (or 585 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 21202402 is about 4604.6066064323. The cubic root of 21202402 is about 276.7759530186.

Adding to 21202402 its reverse (20420212), we get a palindrome (41622614).

The spelling of 21202402 in words is "twenty-one million, two hundred two thousand, four hundred two".