21010000023 has 16 divisors (see below), whose sum is σ = 31332064000. Its totient is φ = 13913904600.

The previous prime is 21010000021. The next prime is 21010000031. The reversal of 21010000023 is 32000001012.

It is a happy number.

It is not a de Polignac number, because 21010000023 - 2¹ = 21010000021 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010000021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2572573 + ... + 2580726.

It is an arithmetic number, because the mean of its divisors is an integer number (1958254000).

Almost surely, 2^21010000023 is an apocalyptic number.

21010000023 is a deficient number, since it is larger than the sum of its proper divisors (10322063977).

21010000023 is a wasteful number, since it uses less digits than its factorization.

21010000023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5153459 (or 5153453 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

Adding to 21010000023 its reverse (32000001012), we get a palindrome (53010001035).

The spelling of 21010000023 in words is "twenty-one billion, ten million, twenty-three", and thus it is an aban number and an uban number.