1231722745 has 16 divisors (see below), whose sum is σ = 1649938752. Its totient is φ = 874964160.

The previous prime is 1231722731. The next prime is 1231722757. The reversal of 1231722745 is 5472271321.

It is not a de Polignac number, because 1231722745 - 2²³ = 1223334137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1231722745.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 258042 + ... + 262771.

It is an arithmetic number, because the mean of its divisors is an integer number (103121172).

Almost surely, 2^1231722745 is an apocalyptic number.

It is an amenable number.

1231722745 is a deficient number, since it is larger than the sum of its proper divisors (418216007).

1231722745 is a wasteful number, since it uses less digits than its factorization.

1231722745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520872.

The product of its digits is 23520, while the sum is 34.

The square root of 1231722745 is about 35095.9078098858. The cubic root of 1231722745 is about 1071.9412585809.

The spelling of 1231722745 in words is "one billion, two hundred thirty-one million, seven hundred twenty-two thousand, seven hundred forty-five".