21202074321 has 4 divisors (see below), whose sum is σ = 28269432432. Its totient is φ = 14134716212.

The previous prime is 21202074281. The next prime is 21202074323. The reversal of 21202074321 is 12347020212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21202074321 - 2⁷ = 21202074193 is a prime.

It is a super-2 number, since 2×21202074321² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21202074291 and 21202074300.

It is not an unprimeable number, because it can be changed into a prime (21202074323) 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, 3533679051 + ... + 3533679056.

It is an arithmetic number, because the mean of its divisors is an integer number (7067358108).

Almost surely, 2^21202074321 is an apocalyptic number.

It is an amenable number.

21202074321 is a deficient number, since it is larger than the sum of its proper divisors (7067358111).

21202074321 is an equidigital number, since it uses as much as digits as its factorization.

21202074321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7067358110.

The product of its (nonzero) digits is 1344, while the sum is 24.

Adding to 21202074321 its reverse (12347020212), we get a palindrome (33549094533).

The spelling of 21202074321 in words is "twenty-one billion, two hundred two million, seventy-four thousand, three hundred twenty-one".