1231223101 has 4 divisors (see below), whose sum is σ = 1273679100. Its totient is φ = 1188767104.

The previous prime is 1231223099. The next prime is 1231223111. The reversal of 1231223101 is 1013221321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1013221321 = 7 ⋅144745903.

It can be written as a sum of positive squares in 2 ways, for example, as 256160025 + 975063076 = 16005^2 + 31226^2 .

It is a cyclic number.

It is not a de Polignac number, because 1231223101 - 2¹ = 1231223099 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231223111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21227956 + ... + 21228013.

It is an arithmetic number, because the mean of its divisors is an integer number (318419775).

Almost surely, 2^1231223101 is an apocalyptic number.

It is an amenable number.

1231223101 is a deficient number, since it is larger than the sum of its proper divisors (42455999).

1231223101 is an equidigital number, since it uses as much as digits as its factorization.

1231223101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42455998.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1231223101 is about 35088.7888220725. The cubic root of 1231223101 is about 1071.7962959107.

Adding to 1231223101 its reverse (1013221321), we get a palindrome (2244444422).

The spelling of 1231223101 in words is "one billion, two hundred thirty-one million, two hundred twenty-three thousand, one hundred one".