2121321031 has 4 divisors (see below), whose sum is σ = 2151198864. Its totient is φ = 2091443200.

The previous prime is 2121321011. The next prime is 2121321053. The reversal of 2121321031 is 1301231212.

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 2121321031 - 2¹⁵ = 2121288263 is a prime.

It is a super-2 number, since 2×2121321031² = 9000005833125805922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2121320996 and 2121321014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121321001) 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 3 ways as a sum of consecutive naturals, for example, 14938810 + ... + 14938951.

It is an arithmetic number, because the mean of its divisors is an integer number (537799716).

Almost surely, 2^2121321031 is an apocalyptic number.

2121321031 is a deficient number, since it is larger than the sum of its proper divisors (29877833).

2121321031 is an equidigital number, since it uses as much as digits as its factorization.

2121321031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29877832.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 2121321031 is about 46057.8009787701. The cubic root of 2121321031 is about 1284.8984322211.

Adding to 2121321031 its reverse (1301231212), we get a palindrome (3422552243).

The spelling of 2121321031 in words is "two billion, one hundred twenty-one million, three hundred twenty-one thousand, thirty-one".