20120406221 has 4 divisors (see below), whose sum is σ = 20183877852. Its totient is φ = 20056934592.

The previous prime is 20120406169. The next prime is 20120406227. The reversal of 20120406221 is 12260402102.

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 1937232196 + 18183174025 = 44014^2 + 134845^2 .

It is a cyclic number.

It is not a de Polignac number, because 20120406221 - 2¹⁴ = 20120389837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20120406193 and 20120406202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20120406227) 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, 31735340 + ... + 31735973.

It is an arithmetic number, because the mean of its divisors is an integer number (5045969463).

Almost surely, 2^20120406221 is an apocalyptic number.

It is an amenable number.

20120406221 is a deficient number, since it is larger than the sum of its proper divisors (63471631).

20120406221 is an equidigital number, since it uses as much as digits as its factorization.

20120406221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63471630.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 20120406221 its reverse (12260402102), we get a palindrome (32380808323).

The spelling of 20120406221 in words is "twenty billion, one hundred twenty million, four hundred six thousand, two hundred twenty-one".