21045212454 has 32 divisors (see below), whose sum is σ = 48108856320. Its totient is φ = 6012228672.

The previous prime is 21045212437. The next prime is 21045212473. The reversal of 21045212454 is 45421254012.

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 15 ways as a sum of consecutive naturals, for example, 427267 + ... + 473969.

It is an arithmetic number, because the mean of its divisors is an integer number (1503401760).

Almost surely, 2^21045212454 is an apocalyptic number.

21045212454 is an abundant number, since it is smaller than the sum of its proper divisors (27063643866).

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

21045212454 is a wasteful number, since it uses less digits than its factorization.

21045212454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57444.

The product of its (nonzero) digits is 12800, while the sum is 30.

Adding to 21045212454 its reverse (45421254012), we get a palindrome (66466466466).

The spelling of 21045212454 in words is "twenty-one billion, forty-five million, two hundred twelve thousand, four hundred fifty-four".