21250252564241 has 4 divisors (see below), whose sum is σ = 21250446222372. Its totient is φ = 21250058906112.

The previous prime is 21250252564201. The next prime is 21250252564267. The reversal of 21250252564241 is 14246525205212.

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 17633314233616 + 3616938330625 = 4199204^2 + 1901825^2 .

It is a cyclic number.

It is not a de Polignac number, because 21250252564241 - 2¹⁰ = 21250252563217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21250252564201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 96664376 + ... + 96883961.

It is an arithmetic number, because the mean of its divisors is an integer number (5312611555593).

Almost surely, 2^{21250252564241} is an apocalyptic number.

It is an amenable number.

21250252564241 is a deficient number, since it is larger than the sum of its proper divisors (193658131).

21250252564241 is a wasteful number, since it uses less digits than its factorization.

21250252564241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193658130.

The product of its (nonzero) digits is 384000, while the sum is 41.

Adding to 21250252564241 its reverse (14246525205212), we get a palindrome (35496777769453).

The spelling of 21250252564241 in words is "twenty-one trillion, two hundred fifty billion, two hundred fifty-two million, five hundred sixty-four thousand, two hundred forty-one".