21012223134 has 16 divisors (see below), whose sum is σ = 48027938688. Its totient is φ = 6003492312.

The previous prime is 21012223123. The next prime is 21012223163. The reversal of 21012223134 is 43132221012.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 21012223134.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 250145472 + ... + 250145555.

It is an arithmetic number, because the mean of its divisors is an integer number (3001746168).

Almost surely, 2^21012223134 is an apocalyptic number.

21012223134 is an abundant number, since it is smaller than the sum of its proper divisors (27015715554).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21012223134 is a wasteful number, since it uses less digits than its factorization.

21012223134 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500291039.

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21012223134 its reverse (43132221012), we get a palindrome (64144444146).

The spelling of 21012223134 in words is "twenty-one billion, twelve million, two hundred twenty-three thousand, one hundred thirty-four".