21010505235 has 16 divisors (see below), whose sum is σ = 35386114560. Its totient is φ = 10615834080.

The previous prime is 21010505213. The next prime is 21010505297. The reversal of 21010505235 is 53250501012.

It is a happy number.

It is not a de Polignac number, because 21010505235 - 2⁵ = 21010505203 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36860251 + ... + 36860820.

It is an arithmetic number, because the mean of its divisors is an integer number (2211632160).

Almost surely, 2^21010505235 is an apocalyptic number.

21010505235 is a deficient number, since it is larger than the sum of its proper divisors (14375609325).

21010505235 is a wasteful number, since it uses less digits than its factorization.

21010505235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73721098.

The product of its (nonzero) digits is 1500, while the sum is 24.

The spelling of 21010505235 in words is "twenty-one billion, ten million, five hundred five thousand, two hundred thirty-five".