21031320303 has 32 divisors (see below), whose sum is σ = 35721016320. Its totient is φ = 11979951840.

The previous prime is 21031320281. The next prime is 21031320307. The reversal of 21031320303 is 30302313012.

21031320303 is a `hidden beast` number, since 2 + 10 + 31 + 320 + 303 = 666.

It is not a de Polignac number, because 21031320303 - 2⁸ = 21031320047 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21031320307) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 115603 + ... + 235428.

It is an arithmetic number, because the mean of its divisors is an integer number (1116281760).

Almost surely, 2^21031320303 is an apocalyptic number.

21031320303 is a deficient number, since it is larger than the sum of its proper divisors (14689696017).

21031320303 is a wasteful number, since it uses less digits than its factorization.

21031320303 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351364 (or 351358 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 18.

Adding to 21031320303 its reverse (30302313012), we get a palindrome (51333633315).

The spelling of 21031320303 in words is "twenty-one billion, thirty-one million, three hundred twenty thousand, three hundred three".