21051440501255 has 16 divisors (see below), whose sum is σ = 25268700776448. Its totient is φ = 16836504804000.

The previous prime is 21051440501251. The next prime is 21051440501297. The reversal of 21051440501255 is 55210504415012.

It is not a de Polignac number, because 21051440501255 - 2² = 21051440501251 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21051440501251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 589146740 + ... + 589182470.

It is an arithmetic number, because the mean of its divisors is an integer number (1579293798528).

Almost surely, 2^{21051440501255} is an apocalyptic number.

21051440501255 is a deficient number, since it is larger than the sum of its proper divisors (4217260275193).

21051440501255 is a wasteful number, since it uses less digits than its factorization.

21051440501255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64958.

The product of its (nonzero) digits is 40000, while the sum is 35.

Adding to 21051440501255 its reverse (55210504415012), we get a palindrome (76261944916267).

The spelling of 21051440501255 in words is "twenty-one trillion, fifty-one billion, four hundred forty million, five hundred one thousand, two hundred fifty-five".