21280091232 has 48 divisors (see below), whose sum is σ = 56194774272. Its totient is φ = 7050883200.

The previous prime is 21280091201. The next prime is 21280091233. The reversal of 21280091232 is 23219008212.

It is a tau number, because it is divible by the number of its divisors (48).

It is a self number, because there is not a number n which added to its sum of digits gives 21280091232.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21280091233) 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, 647644 + ... + 679707.

It is an arithmetic number, because the mean of its divisors is an integer number (1170724464).

Almost surely, 2^21280091232 is an apocalyptic number.

It is an amenable number.

21280091232 is an abundant number, since it is smaller than the sum of its proper divisors (34914683040).

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

21280091232 is a wasteful number, since it uses less digits than its factorization.

21280091232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1327531 (or 1327523 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

Adding to 21280091232 its reverse (23219008212), we get a palindrome (44499099444).

The spelling of 21280091232 in words is "twenty-one billion, two hundred eighty million, ninety-one thousand, two hundred thirty-two".