21302143 has 2 divisors, whose sum is σ = 21302144. Its totient is φ = 21302142.

The previous prime is 21302129. The next prime is 21302147. The reversal of 21302143 is 34120312.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21302143 - 2⁵ = 21302111 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21302147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10651071 + 10651072.

It is an arithmetic number, because the mean of its divisors is an integer number (10651072).

Almost surely, 2^21302143 is an apocalyptic number.

21302143 is a deficient number, since it is larger than the sum of its proper divisors (1).

21302143 is an equidigital number, since it uses as much as digits as its factorization.

21302143 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 21302143 is about 4615.4244658536. The cubic root of 21302143 is about 277.2092802570.

Adding to 21302143 its reverse (34120312), we get a palindrome (55422455).

The spelling of 21302143 in words is "twenty-one million, three hundred two thousand, one hundred forty-three".