21125410331 has 2 divisors, whose sum is σ = 21125410332. Its totient is φ = 21125410330.

The previous prime is 21125410309. The next prime is 21125410333. The reversal of 21125410331 is 13301452112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21125410331 - 2¹⁰ = 21125409307 is a prime.

It is a super-2 number, since 2×21125410331² (a number of 21 digits) contains 22 as substring.

Together with 21125410333, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21125410297 and 21125410306.

It is not a weakly prime, because it can be changed into another prime (21125410333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10562705165 + 10562705166.

It is an arithmetic number, because the mean of its divisors is an integer number (10562705166).

Almost surely, 2^21125410331 is an apocalyptic number.

21125410331 is a deficient number, since it is larger than the sum of its proper divisors (1).

21125410331 is an equidigital number, since it uses as much as digits as its factorization.

21125410331 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720, while the sum is 23.

Adding to 21125410331 its reverse (13301452112), we get a palindrome (34426862443).

The spelling of 21125410331 in words is "twenty-one billion, one hundred twenty-five million, four hundred ten thousand, three hundred thirty-one".