21500322201 has 6 divisors (see below), whose sum is σ = 31056020970. Its totient is φ = 14333548128.

The previous prime is 21500322197. The next prime is 21500322253. The reversal of 21500322201 is 10222300512.

It can be written as a sum of positive squares in only one way, i.e., 12231254025 + 9269068176 = 110595^2 + 96276^2 .

It is not a de Polignac number, because 21500322201 - 2² = 21500322197 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21500322281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1194462336 + ... + 1194462353.

It is an arithmetic number, because the mean of its divisors is an integer number (5176003495).

Almost surely, 2^21500322201 is an apocalyptic number.

It is an amenable number.

21500322201 is a deficient number, since it is larger than the sum of its proper divisors (9555698769).

21500322201 is a wasteful number, since it uses less digits than its factorization.

21500322201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2388924695 (or 2388924692 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

Adding to 21500322201 its reverse (10222300512), we get a palindrome (31722622713).

The spelling of 21500322201 in words is "twenty-one billion, five hundred million, three hundred twenty-two thousand, two hundred one".