31322130221 has 4 divisors (see below), whose sum is σ = 31751200572. Its totient is φ = 30893059872.

The previous prime is 31322130167. The next prime is 31322130263. The reversal of 31322130221 is 12203122313.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12203122313 = 479 ⋅25476247.

It can be written as a sum of positive squares in 2 ways, for example, as 20181327721 + 11140802500 = 142061^2 + 105550^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31322130221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31322130193 and 31322130202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31322130271) 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, 214535066 + ... + 214535211.

It is an arithmetic number, because the mean of its divisors is an integer number (7937800143).

Almost surely, 2^31322130221 is an apocalyptic number.

It is an amenable number.

31322130221 is a deficient number, since it is larger than the sum of its proper divisors (429070351).

31322130221 is an equidigital number, since it uses as much as digits as its factorization.

31322130221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 429070350.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 31322130221 its reverse (12203122313), we get a palindrome (43525252534).

The spelling of 31322130221 in words is "thirty-one billion, three hundred twenty-two million, one hundred thirty thousand, two hundred twenty-one".