21120220331 has 4 divisors (see below), whose sum is σ = 24137394672. Its totient is φ = 18103045992.

The previous prime is 21120220307. The next prime is 21120220339. The reversal of 21120220331 is 13302202112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21120220331 - 2⁶ = 21120220267 is a prime.

It is a super-2 number, since 2×21120220331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21120220339) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1508587160 + ... + 1508587173.

It is an arithmetic number, because the mean of its divisors is an integer number (6034348668).

Almost surely, 2^21120220331 is an apocalyptic number.

21120220331 is a deficient number, since it is larger than the sum of its proper divisors (3017174341).

21120220331 is an equidigital number, since it uses as much as digits as its factorization.

21120220331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3017174340.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21120220331 its reverse (13302202112), we get a palindrome (34422422443).

The spelling of 21120220331 in words is "twenty-one billion, one hundred twenty million, two hundred twenty thousand, three hundred thirty-one".