21423204201 has 12 divisors (see below), whose sum is σ = 33227827152. Its totient is φ = 12241830888.

The previous prime is 21423204199. The next prime is 21423204217. The reversal of 21423204201 is 10240232412.

It is not a de Polignac number, because 21423204201 - 2¹ = 21423204199 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (21423204701) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 72867895 + ... + 72868188.

It is an arithmetic number, because the mean of its divisors is an integer number (2768985596).

Almost surely, 2^21423204201 is an apocalyptic number.

21423204201 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21423204201 is a deficient number, since it is larger than the sum of its proper divisors (11804622951).

21423204201 is a wasteful number, since it uses less digits than its factorization.

21423204201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145736100 (or 145736093 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 21423204201 its reverse (10240232412), we get a palindrome (31663436613).

The spelling of 21423204201 in words is "twenty-one billion, four hundred twenty-three million, two hundred four thousand, two hundred one".