21211001023 has 4 divisors (see below), whose sum is σ = 21216179800. Its totient is φ = 21205822248.

The previous prime is 21211000973. The next prime is 21211001027. The reversal of 21211001023 is 32010011212.

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 21211001023 - 2⁹ = 21211000511 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21211000994 and 21211001012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211001027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2583240 + ... + 2591437.

It is an arithmetic number, because the mean of its divisors is an integer number (5304044950).

Almost surely, 2^21211001023 is an apocalyptic number.

21211001023 is a deficient number, since it is larger than the sum of its proper divisors (5178777).

21211001023 is an equidigital number, since it uses as much as digits as its factorization.

21211001023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5178776.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21211001023 its reverse (32010011212), we get a palindrome (53221012235).

The spelling of 21211001023 in words is "twenty-one billion, two hundred eleven million, one thousand, twenty-three".