20911831201 has 16 divisors (see below), whose sum is σ = 21232659024. Its totient is φ = 20594294784.

The previous prime is 20911831181. The next prime is 20911831207. The reversal of 20911831201 is 10213811902.

It can be written as a sum of positive squares in 8 ways, for example, as 8798627601 + 12113203600 = 93801^2 + 110060^2 .

It is a cyclic number.

It is not a de Polignac number, because 20911831201 - 2²⁷ = 20777613473 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 20911831201.

It is not an unprimeable number, because it can be changed into a prime (20911831207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8579755 + ... + 8582191.

It is an arithmetic number, because the mean of its divisors is an integer number (1327041189).

Almost surely, 2^20911831201 is an apocalyptic number.

It is an amenable number.

20911831201 is a deficient number, since it is larger than the sum of its proper divisors (320827823).

20911831201 is a wasteful number, since it uses less digits than its factorization.

20911831201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3060.

The product of its (nonzero) digits is 864, while the sum is 28.

The spelling of 20911831201 in words is "twenty billion, nine hundred eleven million, eight hundred thirty-one thousand, two hundred one".