21323210387 has 2 divisors, whose sum is σ = 21323210388. Its totient is φ = 21323210386.

The previous prime is 21323210317. The next prime is 21323210399. The reversal of 21323210387 is 78301232312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21323210387 - 2³² = 17028243091 is a prime.

It is not a weakly prime, because it can be changed into another prime (21323210317) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661605193 + 10661605194.

It is an arithmetic number, because the mean of its divisors is an integer number (10661605194).

Almost surely, 2^21323210387 is an apocalyptic number.

21323210387 is a deficient number, since it is larger than the sum of its proper divisors (1).

21323210387 is an equidigital number, since it uses as much as digits as its factorization.

21323210387 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12096, while the sum is 32.

Adding to 21323210387 its reverse (78301232312), we get a palindrome (99624442699).

The spelling of 21323210387 in words is "twenty-one billion, three hundred twenty-three million, two hundred ten thousand, three hundred eighty-seven".