2102121321 has 4 divisors (see below), whose sum is σ = 2802828432. Its totient is φ = 1401414212.

The previous prime is 2102121311. The next prime is 2102121331. The reversal of 2102121321 is 1231212012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (2102121311) and next prime (2102121331).

It is a cyclic number.

It is not a de Polignac number, because 2102121321 - 2⁶ = 2102121257 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2102121321.

It is not an unprimeable number, because it can be changed into a prime (2102121311) 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 3 ways as a sum of consecutive naturals, for example, 350353551 + ... + 350353556.

It is an arithmetic number, because the mean of its divisors is an integer number (700707108).

Almost surely, 2^2102121321 is an apocalyptic number.

It is an amenable number.

2102121321 is a deficient number, since it is larger than the sum of its proper divisors (700707111).

2102121321 is an equidigital number, since it uses as much as digits as its factorization.

2102121321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700707110.

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

The square root of 2102121321 is about 45848.8966170398. The cubic root of 2102121321 is about 1281.0102134459.

Adding to 2102121321 its reverse (1231212012), we get a palindrome (3333333333).

The spelling of 2102121321 in words is "two billion, one hundred two million, one hundred twenty-one thousand, three hundred twenty-one".