21153144254 has 12 divisors (see below), whose sum is σ = 34876465512. Its totient is φ = 9615065460.

The previous prime is 21153144223. The next prime is 21153144263. The reversal of 21153144254 is 45244135112.

It is a self number, because there is not a number n which added to its sum of digits gives 21153144254.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 43704602 + ... + 43705085.

It is an arithmetic number, because the mean of its divisors is an integer number (2906372126).

Almost surely, 2^21153144254 is an apocalyptic number.

21153144254 is a deficient number, since it is larger than the sum of its proper divisors (13723321258).

21153144254 is a wasteful number, since it uses less digits than its factorization.

21153144254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87409711 (or 87409700 counting only the distinct ones).

The product of its digits is 19200, while the sum is 32.

Adding to 21153144254 its reverse (45244135112), we get a palindrome (66397279366).

The spelling of 21153144254 in words is "twenty-one billion, one hundred fifty-three million, one hundred forty-four thousand, two hundred fifty-four".