21651381153111 has 16 divisors (see below), whose sum is σ = 28975640400000. Its totient is φ = 14380786565088.

The previous prime is 21651381153107. The next prime is 21651381153113. The reversal of 21651381153111 is 11135118315612.

It is not a de Polignac number, because 21651381153111 - 2² = 21651381153107 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21651381153111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21651381153113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11440836 + ... + 13198313.

It is an arithmetic number, because the mean of its divisors is an integer number (1810977525000).

Almost surely, 2^{21651381153111} is an apocalyptic number.

21651381153111 is a deficient number, since it is larger than the sum of its proper divisors (7324259246889).

21651381153111 is a wasteful number, since it uses less digits than its factorization.

21651381153111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24640238.

The product of its digits is 21600, while the sum is 39.

Adding to 21651381153111 its reverse (11135118315612), we get a palindrome (32786499468723).

The spelling of 21651381153111 in words is "twenty-one trillion, six hundred fifty-one billion, three hundred eighty-one million, one hundred fifty-three thousand, one hundred eleven".