21000234135 has 16 divisors (see below), whose sum is σ = 33801578496. Its totient is φ = 11133056928.

The previous prime is 21000234109. The next prime is 21000234163. The reversal of 21000234135 is 53143200012.

It is not a de Polignac number, because 21000234135 - 2⁵ = 21000234103 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, 4189159 + ... + 4194168.

It is an arithmetic number, because the mean of its divisors is an integer number (2112598656).

Almost surely, 2^21000234135 is an apocalyptic number.

21000234135 is a deficient number, since it is larger than the sum of its proper divisors (12801344361).

21000234135 is a wasteful number, since it uses less digits than its factorization.

21000234135 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8383502.

The product of its (nonzero) digits is 720, while the sum is 21.

Adding to 21000234135 its reverse (53143200012), we get a palindrome (74143434147).

The spelling of 21000234135 in words is "twenty-one billion, two hundred thirty-four thousand, one hundred thirty-five".