21132123321 has 8 divisors (see below), whose sum is σ = 28176836544. Its totient is φ = 14087746160.

The previous prime is 21132123317. The next prime is 21132123329. The reversal of 21132123321 is 12332123112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21132123321 - 2² = 21132123317 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21132123329) 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 7 ways as a sum of consecutive naturals, for example, 196795 + ... + 284591.

It is an arithmetic number, because the mean of its divisors is an integer number (3522104568).

Almost surely, 2^21132123321 is an apocalyptic number.

It is an amenable number.

21132123321 is a deficient number, since it is larger than the sum of its proper divisors (7044713223).

21132123321 is an equidigital number, since it uses as much as digits as its factorization.

21132123321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168031.

The product of its digits is 432, while the sum is 21.

Adding to 21132123321 its reverse (12332123112), we get a palindrome (33464246433).

It can be divided in two parts, 21132 and 123321, that added together give a triangular number (144453 = T₅₃₇).

The spelling of 21132123321 in words is "twenty-one billion, one hundred thirty-two million, one hundred twenty-three thousand, three hundred twenty-one".