21512454234055 has 8 divisors (see below), whose sum is σ = 25814976231744. Its totient is φ = 17209942620000.

The previous prime is 21512454234031. The next prime is 21512454234109. The reversal of 21512454234055 is 55043245421512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21512454234055 - 2⁵ = 21512454234023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3096930 + ... + 7253680.

It is an arithmetic number, because the mean of its divisors is an integer number (3226872028968).

Almost surely, 2^{21512454234055} is an apocalyptic number.

21512454234055 is a deficient number, since it is larger than the sum of its proper divisors (4302521997689).

21512454234055 is a wasteful number, since it uses less digits than its factorization.

21512454234055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5191817.

The product of its (nonzero) digits is 960000, while the sum is 43.

Adding to 21512454234055 its reverse (55043245421512), we get a palindrome (76555699655567).

The spelling of 21512454234055 in words is "twenty-one trillion, five hundred twelve billion, four hundred fifty-four million, two hundred thirty-four thousand, fifty-five".