21202401 has 16 divisors (see below), whose sum is σ = 31008960. Its totient is φ = 12779520.

The previous prime is 21202399. The next prime is 21202403. The reversal of 21202401 is 10420212.

It is an interprime number because it is at equal distance from previous prime (21202399) and next prime (21202403).

It is not a de Polignac number, because 21202401 - 2¹ = 21202399 is a prime.

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 15 ways as a sum of consecutive naturals, for example, 4705 + ... + 8033.

It is an arithmetic number, because the mean of its divisors is an integer number (1938060).

Almost surely, 2^21202401 is an apocalyptic number.

It is an amenable number.

21202401 is a deficient number, since it is larger than the sum of its proper divisors (9806559).

21202401 is a wasteful number, since it uses less digits than its factorization.

21202401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3536.

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 21202401 is about 4604.6064978454. The cubic root of 21202401 is about 276.7759486673.

Adding to 21202401 its reverse (10420212), we get a palindrome (31622613).

The spelling of 21202401 in words is "twenty-one million, two hundred two thousand, four hundred one".