21052054441 has 6 divisors (see below), whose sum is σ = 23139861626. Its totient is φ = 19138231200.

The previous prime is 21052054427. The next prime is 21052054459. The reversal of 21052054441 is 14445025012.

It can be written as a sum of positive squares in only one way, i.e., 20169964441 + 882090000 = 142021^2 + 29700^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21052054441 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21052054421) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 86991840 + ... + 86992081.

Almost surely, 2^21052054441 is an apocalyptic number.

It is an amenable number.

21052054441 is a deficient number, since it is larger than the sum of its proper divisors (2087807185).

21052054441 is a wasteful number, since it uses less digits than its factorization.

21052054441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173983943 (or 173983932 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 28.

Adding to 21052054441 its reverse (14445025012), we get a palindrome (35497079453).

The spelling of 21052054441 in words is "twenty-one billion, fifty-two million, fifty-four thousand, four hundred forty-one".