21201120321 has 8 divisors (see below), whose sum is σ = 28278786240. Its totient is φ = 14128767312.

The previous prime is 21201120301. The next prime is 21201120337. The reversal of 21201120321 is 12302110212.

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

It is not a de Polignac number, because 21201120321 - 2²³ = 21192731713 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21201120321.

It is not an unprimeable number, because it can be changed into a prime (21201120301) 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, 1318906 + ... + 1334883.

It is an arithmetic number, because the mean of its divisors is an integer number (3534848280).

Almost surely, 2^21201120321 is an apocalyptic number.

It is an amenable number.

21201120321 is a deficient number, since it is larger than the sum of its proper divisors (7077665919).

21201120321 is a wasteful number, since it uses less digits than its factorization.

21201120321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2656455.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21201120321 its reverse (12302110212), we get a palindrome (33503230533).

The spelling of 21201120321 in words is "twenty-one billion, two hundred one million, one hundred twenty thousand, three hundred twenty-one".