21315236303 has 2 divisors, whose sum is σ = 21315236304. Its totient is φ = 21315236302.

The previous prime is 21315236233. The next prime is 21315236351. The reversal of 21315236303 is 30363251312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21315236303 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21315236603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10657618151 + 10657618152.

It is an arithmetic number, because the mean of its divisors is an integer number (10657618152).

Almost surely, 2^21315236303 is an apocalyptic number.

21315236303 is a deficient number, since it is larger than the sum of its proper divisors (1).

21315236303 is an equidigital number, since it uses as much as digits as its factorization.

21315236303 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9720, while the sum is 29.

Adding to 21315236303 its reverse (30363251312), we get a palindrome (51678487615).

The spelling of 21315236303 in words is "twenty-one billion, three hundred fifteen million, two hundred thirty-six thousand, three hundred three".