21141500221 has 4 divisors (see below), whose sum is σ = 21870517500. Its totient is φ = 20412482944.

The previous prime is 21141500141. The next prime is 21141500251. The reversal of 21141500221 is 12200514112.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14803588900 + 6337911321 = 121670^2 + 79611^2 .

It is a cyclic number.

It is not a de Polignac number, because 21141500221 - 2¹¹ = 21141498173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21141500251) 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 3 ways as a sum of consecutive naturals, for example, 364508596 + ... + 364508653.

It is an arithmetic number, because the mean of its divisors is an integer number (5467629375).

Almost surely, 2^21141500221 is an apocalyptic number.

It is an amenable number.

21141500221 is a deficient number, since it is larger than the sum of its proper divisors (729017279).

21141500221 is an equidigital number, since it uses as much as digits as its factorization.

21141500221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 729017278.

The product of its (nonzero) digits is 160, while the sum is 19.

The spelling of 21141500221 in words is "twenty-one billion, one hundred forty-one million, five hundred thousand, two hundred twenty-one".