21312100003 has 4 divisors (see below), whose sum is σ = 21313610568. Its totient is φ = 21310589440.

The previous prime is 21312099983. The next prime is 21312100021. The reversal of 21312100003 is 30000121312.

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 21312100003 - 2¹³ = 21312091811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21312109003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 733918 + ... + 762403.

It is an arithmetic number, because the mean of its divisors is an integer number (5328402642).

Almost surely, 2^21312100003 is an apocalyptic number.

21312100003 is a deficient number, since it is larger than the sum of its proper divisors (1510565).

21312100003 is a wasteful number, since it uses less digits than its factorization.

21312100003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1510564.

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21312100003 its reverse (30000121312), we get a palindrome (51312221315).

The spelling of 21312100003 in words is "twenty-one billion, three hundred twelve million, one hundred thousand, three".