31122101 has 2 divisors, whose sum is σ = 31122102. Its totient is φ = 31122100.

The previous prime is 31122089. The next prime is 31122173. The reversal of 31122101 is 10122113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28143025 + 2979076 = 5305^2 + 1726^2 .

It is an emirp because it is prime and its reverse (10122113) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31122101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31122401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15561050 + 15561051.

It is an arithmetic number, because the mean of its divisors is an integer number (15561051).

Almost surely, 2^31122101 is an apocalyptic number.

It is an amenable number.

31122101 is a deficient number, since it is larger than the sum of its proper divisors (1).

31122101 is an equidigital number, since it uses as much as digits as its factorization.

31122101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 31122101 is about 5578.7185804627. The cubic root of 31122101 is about 314.5499611846.

Adding to 31122101 its product of nonzero digits (12), we get a palindrome (31122113).

Adding to 31122101 its reverse (10122113), we get a palindrome (41244214).

The spelling of 31122101 in words is "thirty-one million, one hundred twenty-two thousand, one hundred one".