20120321 has 4 divisors (see below), whose sum is σ = 21668052. Its totient is φ = 18572592.

The previous prime is 20120281. The next prime is 20120323. The reversal of 20120321 is 12302102.

It is a happy number.

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 5382400 + 14737921 = 2320^2 + 3839^2 .

It is a cyclic number.

It is not a de Polignac number, because 20120321 - 2⁶ = 20120257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20120323) 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, 773846 + ... + 773871.

It is an arithmetic number, because the mean of its divisors is an integer number (5417013).

Almost surely, 2^20120321 is an apocalyptic number.

It is an amenable number.

20120321 is a deficient number, since it is larger than the sum of its proper divisors (1547731).

20120321 is a wasteful number, since it uses less digits than its factorization.

20120321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1547730.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 20120321 is about 4485.5680799649. The cubic root of 20120321 is about 271.9850094463.

Adding to 20120321 its reverse (12302102), we get a palindrome (32422423).

The spelling of 20120321 in words is "twenty million, one hundred twenty thousand, three hundred twenty-one".