21120031001 has 6 divisors (see below), whose sum is σ = 22290116202. Its totient is φ = 20008450080.

The previous prime is 21120030983. The next prime is 21120031007. The reversal of 21120031001 is 10013002112.

It can be written as a sum of positive squares in only one way, i.e., 18177510976 + 2942520025 = 134824^2 + 54245^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21120031001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21120031007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 29251760 + ... + 29252481.

It is an arithmetic number, because the mean of its divisors is an integer number (3715019367).

Almost surely, 2^21120031001 is an apocalyptic number.

It is an amenable number.

21120031001 is a deficient number, since it is larger than the sum of its proper divisors (1170085201).

21120031001 is an equidigital number, since it uses as much as digits as its factorization.

21120031001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58504279 (or 58504260 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 11.

Adding to 21120031001 its reverse (10013002112), we get a palindrome (31133033113).

The spelling of 21120031001 in words is "twenty-one billion, one hundred twenty million, thirty-one thousand, one".