1323639861 has 16 divisors (see below), whose sum is σ = 1810252800. Its totient is φ = 859951040.

The previous prime is 1323639833. The next prime is 1323639917. The reversal of 1323639861 is 1689363231.

It is a cyclic number.

It is not a de Polignac number, because 1323639861 - 2⁹ = 1323639349 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1323639661) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4245 + ... + 51626.

It is an arithmetic number, because the mean of its divisors is an integer number (113140800).

Almost surely, 2^1323639861 is an apocalyptic number.

It is an amenable number.

1323639861 is a deficient number, since it is larger than the sum of its proper divisors (486612939).

1323639861 is a wasteful number, since it uses less digits than its factorization.

1323639861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56076.

The product of its digits is 139968, while the sum is 42.

The square root of 1323639861 is about 36381.8617033268. The cubic root of 1323639861 is about 1097.9686646045.

The spelling of 1323639861 in words is "one billion, three hundred twenty-three million, six hundred thirty-nine thousand, eight hundred sixty-one".