21145142243253 has 32 divisors (see below), whose sum is σ = 32704752050176. Its totient is φ = 11901624280128.

The previous prime is 21145142243227. The next prime is 21145142243279. The reversal of 21145142243253 is 35234224154112.

It is an interprime number because it is at equal distance from previous prime (21145142243227) and next prime (21145142243279).

It is not a de Polignac number, because 21145142243253 - 2⁸ = 21145142242997 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21145142243153) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16801500 + ... + 18016122.

It is an arithmetic number, because the mean of its divisors is an integer number (1022023501568).

Almost surely, 2^{21145142243253} is an apocalyptic number.

It is an amenable number.

21145142243253 is a deficient number, since it is larger than the sum of its proper divisors (11559609806923).

21145142243253 is a wasteful number, since it uses less digits than its factorization.

21145142243253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1227073.

The product of its digits is 230400, while the sum is 39.

Adding to 21145142243253 its reverse (35234224154112), we get a palindrome (56379366397365).

The spelling of 21145142243253 in words is "twenty-one trillion, one hundred forty-five billion, one hundred forty-two million, two hundred forty-three thousand, two hundred fifty-three".