21097287203 has 4 divisors (see below), whose sum is σ = 22207670760. Its totient is φ = 19986903648.

The previous prime is 21097287179. The next prime is 21097287209. The reversal of 21097287203 is 30278279012.

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 21097287203 - 2²⁴ = 21080509987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21097287209) 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, 555191750 + ... + 555191787.

It is an arithmetic number, because the mean of its divisors is an integer number (5551917690).

Almost surely, 2^21097287203 is an apocalyptic number.

21097287203 is a deficient number, since it is larger than the sum of its proper divisors (1110383557).

21097287203 is a wasteful number, since it uses less digits than its factorization.

21097287203 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1110383556.

The product of its (nonzero) digits is 84672, while the sum is 41.

The spelling of 21097287203 in words is "twenty-one billion, ninety-seven million, two hundred eighty-seven thousand, two hundred three".