21251525011255 has 16 divisors (see below), whose sum is σ = 31794489368064. Its totient is φ = 13247703902880.

The previous prime is 21251525011217. The next prime is 21251525011261. The reversal of 21251525011255 is 55211052515212.

It is not a de Polignac number, because 21251525011255 - 2⁷ = 21251525011127 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 15 ways as a sum of consecutive naturals, for example, 27599382747 + ... + 27599383516.

It is an arithmetic number, because the mean of its divisors is an integer number (1987155585504).

Almost surely, 2^{21251525011255} is an apocalyptic number.

21251525011255 is a deficient number, since it is larger than the sum of its proper divisors (10542964356809).

21251525011255 is a wasteful number, since it uses less digits than its factorization.

21251525011255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55198766286.

The product of its (nonzero) digits is 50000, while the sum is 37.

Adding to 21251525011255 its reverse (55211052515212), we get a palindrome (76462577526467).

The spelling of 21251525011255 in words is "twenty-one trillion, two hundred fifty-one billion, five hundred twenty-five million, eleven thousand, two hundred fifty-five".