21025330423 has 16 divisors (see below), whose sum is σ = 22159728576. Its totient is φ = 19909711360.

The previous prime is 21025330421. The next prime is 21025330457. The reversal of 21025330423 is 32403352012.

It is a cyclic number.

It is not a de Polignac number, because 21025330423 - 2¹ = 21025330421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21025330421) 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 in 15 ways as a sum of consecutive naturals, for example, 2441361 + ... + 2449957.

It is an arithmetic number, because the mean of its divisors is an integer number (1384983036).

Almost surely, 2^21025330423 is an apocalyptic number.

21025330423 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21025330423 is a deficient number, since it is larger than the sum of its proper divisors (1134398153).

21025330423 is a wasteful number, since it uses less digits than its factorization.

21025330423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9674.

The product of its (nonzero) digits is 4320, while the sum is 25.

Adding to 21025330423 its reverse (32403352012), we get a palindrome (53428682435).

The spelling of 21025330423 in words is "twenty-one billion, twenty-five million, three hundred thirty thousand, four hundred twenty-three".