21414230021 has 4 divisors (see below), whose sum is σ = 21414524844. Its totient is φ = 21413935200.

The previous prime is 21414229999. The next prime is 21414230039. The reversal of 21414230021 is 12003241412.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 12748668100 + 8665561921 = 112910^2 + 93089^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21414230021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21414229975 and 21414230002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21414230521) 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, 47051 + ... + 212231.

It is an arithmetic number, because the mean of its divisors is an integer number (5353631211).

Almost surely, 2^21414230021 is an apocalyptic number.

It is an amenable number.

21414230021 is a deficient number, since it is larger than the sum of its proper divisors (294823).

21414230021 is a wasteful number, since it uses less digits than its factorization.

21414230021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294822.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21414230021 its reverse (12003241412), we get a palindrome (33417471433).

The spelling of 21414230021 in words is "twenty-one billion, four hundred fourteen million, two hundred thirty thousand, twenty-one".