21055124529 has 28 divisors (see below), whose sum is σ = 33425220996. Its totient is φ = 13211050752.

The previous prime is 21055124527. The next prime is 21055124539. The reversal of 21055124529 is 92542155012.

21055124529 is a `hidden beast` number, since 2 + 1 + 0 + 5 + 5 + 124 + 529 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 14598680625 + 6456443904 = 120825^2 + 80352^2 .

It is not a de Polignac number, because 21055124529 - 2¹ = 21055124527 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21055124493 and 21055124502.

It is not an unprimeable number, because it can be changed into a prime (21055124527) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 837084 + ... + 861869.

Almost surely, 2^21055124529 is an apocalyptic number.

It is an amenable number.

21055124529 is a deficient number, since it is larger than the sum of its proper divisors (12370096467).

21055124529 is an equidigital number, since it uses as much as digits as its factorization.

21055124529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1698988 (or 1698973 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The spelling of 21055124529 in words is "twenty-one billion, fifty-five million, one hundred twenty-four thousand, five hundred twenty-nine".