21123402230 has 32 divisors (see below), whose sum is σ = 44378413056. Its totient is φ = 7088216544.

The previous prime is 21123402217. The next prime is 21123402233. The reversal of 21123402230 is 3220432112.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123402233) 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, 3206954 + ... + 3213533.

It is an arithmetic number, because the mean of its divisors is an integer number (1386825408).

Almost surely, 2^21123402230 is an apocalyptic number.

21123402230 is an abundant number, since it is smaller than the sum of its proper divisors (23255010826).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21123402230 is a wasteful number, since it uses less digits than its factorization.

21123402230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6420548.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21123402230 its reverse (3220432112), we get a palindrome (24343834342).

The spelling of 21123402230 in words is "twenty-one billion, one hundred twenty-three million, four hundred two thousand, two hundred thirty".