21210210023 has 6 divisors (see below), whose sum is σ = 21431135736. Its totient is φ = 20991538752.

The previous prime is 21210210011. The next prime is 21210210031. The reversal of 21210210023 is 32001201212.

It is a happy number.

It is not a de Polignac number, because 21210210023 - 2⁶ = 21210209959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210210053) 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 5 ways as a sum of consecutive naturals, for example, 1117715 + ... + 1136532.

It is an arithmetic number, because the mean of its divisors is an integer number (3571855956).

Almost surely, 2^21210210023 is an apocalyptic number.

21210210023 is a deficient number, since it is larger than the sum of its proper divisors (220925713).

21210210023 is an frugal number, since it uses more digits than its factorization.

21210210023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2254441 (or 2254344 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21210210023 its reverse (32001201212), we get a palindrome (53211411235).

The spelling of 21210210023 in words is "twenty-one billion, two hundred ten million, two hundred ten thousand, twenty-three".