21123432304 has 40 divisors (see below), whose sum is σ = 44570116080. Its totient is φ = 9639725568.

The previous prime is 21123432259. The next prime is 21123432307. The reversal of 21123432304 is 40323432112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123432307) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 552022 + ... + 589045.

It is an arithmetic number, because the mean of its divisors is an integer number (1114252902).

Almost surely, 2^21123432304 is an apocalyptic number.

It is an amenable number.

21123432304 is an abundant number, since it is smaller than the sum of its proper divisors (23446683776).

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

21123432304 is a wasteful number, since it uses less digits than its factorization.

21123432304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1141177 (or 1141171 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21123432304 its reverse (40323432112), we get a palindrome (61446864416).

The spelling of 21123432304 in words is "twenty-one billion, one hundred twenty-three million, four hundred thirty-two thousand, three hundred four".