21113204231051 has 4 divisors (see below), whose sum is σ = 21113321850600. Its totient is φ = 21113086611504.

The previous prime is 21113204231029. The next prime is 21113204231059. The reversal of 21113204231051 is 15013240231112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21113204231051 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21113204231051.

It is not an unprimeable number, because it can be changed into a prime (21113204231059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58540106 + ... + 58899663.

It is an arithmetic number, because the mean of its divisors is an integer number (5278330462650).

Almost surely, 2^{21113204231051} is an apocalyptic number.

21113204231051 is a deficient number, since it is larger than the sum of its proper divisors (117619549).

21113204231051 is a wasteful number, since it uses less digits than its factorization.

21113204231051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 117619548.

The product of its (nonzero) digits is 1440, while the sum is 26.

Adding to 21113204231051 its reverse (15013240231112), we get a palindrome (36126444462163).

The spelling of 21113204231051 in words is "twenty-one trillion, one hundred thirteen billion, two hundred four million, two hundred thirty-one thousand, fifty-one".