21000241253 has 8 divisors (see below), whose sum is σ = 22236900480. Its totient is φ = 19763732160.

The previous prime is 21000241183. The next prime is 21000241261. The reversal of 21000241253 is 35214200012.

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

It is not a de Polignac number, because 21000241253 - 2²⁰ = 20999192677 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 (21000241553) 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, 389108 + ... + 439778.

It is an arithmetic number, because the mean of its divisors is an integer number (2779612560).

Almost surely, 2^21000241253 is an apocalyptic number.

It is an amenable number.

21000241253 is a deficient number, since it is larger than the sum of its proper divisors (1236659227).

21000241253 is a wasteful number, since it uses less digits than its factorization.

21000241253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75067.

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 21000241253 its reverse (35214200012), we get a palindrome (56214441265).

The spelling of 21000241253 in words is "twenty-one billion, two hundred forty-one thousand, two hundred fifty-three".