21512414450454 has 16 divisors (see below), whose sum is σ = 43334360045760. Its totient is φ = 7119216292680.

The previous prime is 21512414450441. The next prime is 21512414450489. The reversal of 21512414450454 is 45405441421512.

It is a super-2 number, since 2×21512414450454² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12897130132 + ... + 12897131799.

It is an arithmetic number, because the mean of its divisors is an integer number (2708397502860).

Almost surely, 2^{21512414450454} is an apocalyptic number.

21512414450454 is an abundant number, since it is smaller than the sum of its proper divisors (21821945595306).

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

21512414450454 is a wasteful number, since it uses less digits than its factorization.

21512414450454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25794262075.

The product of its (nonzero) digits is 512000, while the sum is 42.

Adding to 21512414450454 its reverse (45405441421512), we get a palindrome (66917855871966).

The spelling of 21512414450454 in words is "twenty-one trillion, five hundred twelve billion, four hundred fourteen million, four hundred fifty thousand, four hundred fifty-four".