1231321705 has 32 divisors (see below), whose sum is σ = 1596423168. Its totient is φ = 909792000.

The previous prime is 1231321703. The next prime is 1231321709. The reversal of 1231321705 is 5071231321.

It is a happy number.

It is not a de Polignac number, because 1231321705 - 2¹ = 1231321703 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1231321705.

It is not an unprimeable number, because it can be changed into a prime (1231321703) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 301930 + ... + 305980.

It is an arithmetic number, because the mean of its divisors is an integer number (49888224).

Almost surely, 2^1231321705 is an apocalyptic number.

It is an amenable number.

1231321705 is a deficient number, since it is larger than the sum of its proper divisors (365101463).

1231321705 is a wasteful number, since it uses less digits than its factorization.

1231321705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4177.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 1231321705 is about 35090.1938581137. The cubic root of 1231321705 is about 1071.8249071837.

The spelling of 1231321705 in words is "one billion, two hundred thirty-one million, three hundred twenty-one thousand, seven hundred five".