21500541201 has 4 divisors (see below), whose sum is σ = 28667388272. Its totient is φ = 14333694132.

The previous prime is 21500541173. The next prime is 21500541221. The reversal of 21500541201 is 10214500512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21500541201 - 2⁵ = 21500541169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21500541221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3583423531 + ... + 3583423536.

It is an arithmetic number, because the mean of its divisors is an integer number (7166847068).

Almost surely, 2^21500541201 is an apocalyptic number.

It is an amenable number.

21500541201 is a deficient number, since it is larger than the sum of its proper divisors (7166847071).

21500541201 is an equidigital number, since it uses as much as digits as its factorization.

21500541201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7166847070.

The product of its (nonzero) digits is 400, while the sum is 21.

The spelling of 21500541201 in words is "twenty-one billion, five hundred million, five hundred forty-one thousand, two hundred one".