12021005591 has 16 divisors (see below), whose sum is σ = 14723065344. Its totient is φ = 9589355424.

The previous prime is 12021005587. The next prime is 12021005593. The reversal of 12021005591 is 19550012021.

It is a cyclic number.

It is not a de Polignac number, because 12021005591 - 2² = 12021005587 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 12021005591.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12021005593) 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, 1003025 + ... + 1014938.

It is an arithmetic number, because the mean of its divisors is an integer number (920191584).

Almost surely, 2^12021005591 is an apocalyptic number.

12021005591 is a deficient number, since it is larger than the sum of its proper divisors (2702059753).

12021005591 is a wasteful number, since it uses less digits than its factorization.

12021005591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2018030.

The product of its (nonzero) digits is 900, while the sum is 26.

The spelling of 12021005591 in words is "twelve billion, twenty-one million, five thousand, five hundred ninety-one".