21042000255 has 16 divisors (see below), whose sum is σ = 33669185760. Its totient is φ = 11221738368.

The previous prime is 21042000229. The next prime is 21042000277. The reversal of 21042000255 is 55200024012.

It is a happy number.

It is not a de Polignac number, because 21042000255 - 2¹⁹ = 21041475967 is a prime.

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, 327741 + ... + 386649.

It is an arithmetic number, because the mean of its divisors is an integer number (2104324110).

Almost surely, 2^21042000255 is an apocalyptic number.

21042000255 is a deficient number, since it is larger than the sum of its proper divisors (12627185505).

21042000255 is a wasteful number, since it uses less digits than its factorization.

21042000255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82730.

The product of its (nonzero) digits is 800, while the sum is 21.

Adding to 21042000255 its reverse (55200024012), we get a palindrome (76242024267).

The spelling of 21042000255 in words is "twenty-one billion, forty-two million, two hundred fifty-five", and thus it is an aban number.