21431410321 has 4 divisors (see below), whose sum is σ = 22170424500. Its totient is φ = 20692396144.

The previous prime is 21431410303. The next prime is 21431410369. The reversal of 21431410321 is 12301413412.

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 14391361296 + 7040049025 = 119964^2 + 83905^2 .

It is a cyclic number.

It is not a de Polignac number, because 21431410321 - 2¹⁵ = 21431377553 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21431410292 and 21431410301.

It is not an unprimeable number, because it can be changed into a prime (21431410391) 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, 369507046 + ... + 369507103.

It is an arithmetic number, because the mean of its divisors is an integer number (5542606125).

Almost surely, 2^21431410321 is an apocalyptic number.

It is an amenable number.

21431410321 is a deficient number, since it is larger than the sum of its proper divisors (739014179).

21431410321 is an equidigital number, since it uses as much as digits as its factorization.

21431410321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 739014178.

The product of its (nonzero) digits is 576, while the sum is 22.

Adding to 21431410321 its reverse (12301413412), we get a palindrome (33732823733).

The spelling of 21431410321 in words is "twenty-one billion, four hundred thirty-one million, four hundred ten thousand, three hundred twenty-one".