21052220541 has 8 divisors (see below), whose sum is σ = 30621411744. Its totient is φ = 12758921520.

The previous prime is 21052220477. The next prime is 21052220543. The reversal of 21052220541 is 14502225012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21052220541 - 2⁶ = 21052220477 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21052220543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 318973006 + ... + 318973071.

It is an arithmetic number, because the mean of its divisors is an integer number (3827676468).

Almost surely, 2^21052220541 is an apocalyptic number.

It is an amenable number.

21052220541 is a deficient number, since it is larger than the sum of its proper divisors (9569191203).

21052220541 is a wasteful number, since it uses less digits than its factorization.

21052220541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637946091.

The product of its (nonzero) digits is 1600, while the sum is 24.

Adding to 21052220541 its reverse (14502225012), we get a palindrome (35554445553).

The spelling of 21052220541 in words is "twenty-one billion, fifty-two million, two hundred twenty thousand, five hundred forty-one".