21310311403 has 4 divisors (see below), whose sum is σ = 22431906760. Its totient is φ = 20188716048.

The previous prime is 21310311397. The next prime is 21310311419. The reversal of 21310311403 is 30411301312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21310311403 - 2²⁵ = 21276756971 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 1121595337 = 21310311403 / (2 + 1 + 3 + 1 + 0 + 3 + 1 + 1 + 4 + 0 + 3).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21310311103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 560797650 + ... + 560797687.

It is an arithmetic number, because the mean of its divisors is an integer number (5607976690).

Almost surely, 2^21310311403 is an apocalyptic number.

21310311403 is a deficient number, since it is larger than the sum of its proper divisors (1121595357).

21310311403 is a wasteful number, since it uses less digits than its factorization.

21310311403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1121595356.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21310311403 its reverse (30411301312), we get a palindrome (51721612715).

The spelling of 21310311403 in words is "twenty-one billion, three hundred ten million, three hundred eleven thousand, four hundred three".