21202005427 has 2 divisors, whose sum is σ = 21202005428. Its totient is φ = 21202005426.

The previous prime is 21202005397. The next prime is 21202005443. The reversal of 21202005427 is 72450020212.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21202005427 is a prime.

It is not a weakly prime, because it can be changed into another prime (21202005457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601002713 + 10601002714.

It is an arithmetic number, because the mean of its divisors is an integer number (10601002714).

Almost surely, 2^21202005427 is an apocalyptic number.

21202005427 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202005427 is an equidigital number, since it uses as much as digits as its factorization.

21202005427 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2240, while the sum is 25.

Adding to 21202005427 its reverse (72450020212), we get a palindrome (93652025639).

The spelling of 21202005427 in words is "twenty-one billion, two hundred two million, five thousand, four hundred twenty-seven".