1231306109 has 4 divisors (see below), whose sum is σ = 1343243040. Its totient is φ = 1119369180.

The previous prime is 1231306103. The next prime is 1231306129. The reversal of 1231306109 is 9016031321.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1231306109 - 2⁴ = 1231306093 is a prime.

It is a super-2 number, since 2×1231306109² = 3032229468121439762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1231306103) 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, 55968449 + ... + 55968470.

It is an arithmetic number, because the mean of its divisors is an integer number (335810760).

Almost surely, 2^1231306109 is an apocalyptic number.

It is an amenable number.

1231306109 is a deficient number, since it is larger than the sum of its proper divisors (111936931).

1231306109 is a wasteful number, since it uses less digits than its factorization.

1231306109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111936930.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 1231306109 is about 35089.9716300826. The cubic root of 1231306109 is about 1071.8203818968.

The spelling of 1231306109 in words is "one billion, two hundred thirty-one million, three hundred six thousand, one hundred nine".