20101321 has 4 divisors (see below), whose sum is σ = 20794500. Its totient is φ = 19408144.

The previous prime is 20101309. The next prime is 20101331. The reversal of 20101321 is 12310102.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14288400 + 5812921 = 3780^2 + 2411^2 .

It is a cyclic number.

It is not a de Polignac number, because 20101321 - 2⁹ = 20100809 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20101298 and 20101307.

It is not an unprimeable number, because it can be changed into a prime (20101331) 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, 346546 + ... + 346603.

It is an arithmetic number, because the mean of its divisors is an integer number (5198625).

Almost surely, 2^20101321 is an apocalyptic number.

It is an amenable number.

20101321 is a deficient number, since it is larger than the sum of its proper divisors (693179).

20101321 is an equidigital number, since it uses as much as digits as its factorization.

20101321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693178.

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 20101321 is about 4483.4496763095. The cubic root of 20101321 is about 271.8993689523.

Adding to 20101321 its reverse (12310102), we get a palindrome (32411423).

The spelling of 20101321 in words is "twenty million, one hundred one thousand, three hundred twenty-one".