21000254241 has 16 divisors (see below), whose sum is σ = 31207809600. Its totient is φ = 12483122688.

The previous prime is 21000254227. The next prime is 21000254311. The reversal of 21000254241 is 14245200012.

It is not a de Polignac number, because 21000254241 - 2⁷ = 21000254113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21000254641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10835076 + ... + 10837013.

It is an arithmetic number, because the mean of its divisors is an integer number (1950488100).

Almost surely, 2^21000254241 is an apocalyptic number.

It is an amenable number.

21000254241 is a deficient number, since it is larger than the sum of its proper divisors (10207555359).

21000254241 is a wasteful number, since it uses less digits than its factorization.

21000254241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21672128.

The product of its (nonzero) digits is 640, while the sum is 21.

Adding to 21000254241 its reverse (14245200012), we get a palindrome (35245454253).

The spelling of 21000254241 in words is "twenty-one billion, two hundred fifty-four thousand, two hundred forty-one".