1864288221 has 16 divisors (see below), whose sum is σ = 2643249024. Its totient is φ = 1164721664.

The previous prime is 1864288219. The next prime is 1864288243. The reversal of 1864288221 is 1228824681.

It is a cyclic number.

It is not a de Polignac number, because 1864288221 - 2¹ = 1864288219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1864288201) 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, 66561 + ... + 90326.

It is an arithmetic number, because the mean of its divisors is an integer number (165203064).

Almost surely, 2^1864288221 is an apocalyptic number.

It is an amenable number.

1864288221 is a deficient number, since it is larger than the sum of its proper divisors (778960803).

1864288221 is a wasteful number, since it uses less digits than its factorization.

1864288221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157140.

The product of its digits is 98304, while the sum is 42.

The square root of 1864288221 is about 43177.4040558253. The cubic root of 1864288221 is about 1230.7533272722.

The spelling of 1864288221 in words is "one billion, eight hundred sixty-four million, two hundred eighty-eight thousand, two hundred twenty-one".