21413132021 has 4 divisors (see below), whose sum is σ = 21653729100. Its totient is φ = 21172534944.

The previous prime is 21413132009. The next prime is 21413132087. The reversal of 21413132021 is 12023131412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13897108996 + 7516023025 = 117886^2 + 86695^2 .

It is a cyclic number.

It is not a de Polignac number, because 21413132021 - 2¹⁴ = 21413115637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21413131984 and 21413132002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21413132921) 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, 120298406 + ... + 120298583.

It is an arithmetic number, because the mean of its divisors is an integer number (5413432275).

Almost surely, 2^21413132021 is an apocalyptic number.

It is an amenable number.

21413132021 is a deficient number, since it is larger than the sum of its proper divisors (240597079).

21413132021 is an equidigital number, since it uses as much as digits as its factorization.

21413132021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240597078.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21413132021 its reverse (12023131412), we get a palindrome (33436263433).

The spelling of 21413132021 in words is "twenty-one billion, four hundred thirteen million, one hundred thirty-two thousand, twenty-one".