21154300254 has 16 divisors (see below), whose sum is σ = 47009556240. Its totient is φ = 7051433400.

The previous prime is 21154300213. The next prime is 21154300283. The reversal of 21154300254 is 45200345112.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195873097 + ... + 195873204.

It is an arithmetic number, because the mean of its divisors is an integer number (2938097265).

Almost surely, 2^21154300254 is an apocalyptic number.

21154300254 is an abundant number, since it is smaller than the sum of its proper divisors (25855255986).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21154300254 is a wasteful number, since it uses less digits than its factorization.

21154300254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391746312 (or 391746306 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

Adding to 21154300254 its reverse (45200345112), we get a palindrome (66354645366).

The spelling of 21154300254 in words is "twenty-one billion, one hundred fifty-four million, three hundred thousand, two hundred fifty-four".