21023102431 has 2 divisors, whose sum is σ = 21023102432. Its totient is φ = 21023102430.

The previous prime is 21023102407. The next prime is 21023102449. The reversal of 21023102431 is 13420132012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21023102431 - 2⁹ = 21023101919 is a prime.

It is a super-2 number, since 2×21023102431² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21023102399 and 21023102408.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21023102531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511551215 + 10511551216.

It is an arithmetic number, because the mean of its divisors is an integer number (10511551216).

Almost surely, 2^21023102431 is an apocalyptic number.

21023102431 is a deficient number, since it is larger than the sum of its proper divisors (1).

21023102431 is an equidigital number, since it uses as much as digits as its factorization.

21023102431 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 21023102431 its reverse (13420132012), we get a palindrome (34443234443).

The spelling of 21023102431 in words is "twenty-one billion, twenty-three million, one hundred two thousand, four hundred thirty-one".