21200010423 has 4 divisors (see below), whose sum is σ = 28266680568. Its totient is φ = 14133340280.

The previous prime is 21200010383. The next prime is 21200010427. The reversal of 21200010423 is 32401000212.

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 21200010423 - 2¹⁸ = 21199748279 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200010427) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3533335068 + ... + 3533335073.

It is an arithmetic number, because the mean of its divisors is an integer number (7066670142).

Almost surely, 2^21200010423 is an apocalyptic number.

21200010423 is a deficient number, since it is larger than the sum of its proper divisors (7066670145).

21200010423 is an equidigital number, since it uses as much as digits as its factorization.

21200010423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7066670144.

The product of its (nonzero) digits is 96, while the sum is 15.

Adding to 21200010423 its reverse (32401000212), we get a palindrome (53601010635).

The spelling of 21200010423 in words is "twenty-one billion, two hundred million, ten thousand, four hundred twenty-three".