21118107706776 has 384 divisors, whose sum is σ = 60875808215040. Its totient is φ = 6856030771200.

The previous prime is 21118107706769. The next prime is 21118107706777. The reversal of 21118107706776 is 67760770181112.

It is a super-2 number, since 2×21118107706776² (a number of 27 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21118107706777) 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 95 ways as a sum of consecutive naturals, for example, 13598265616 + ... + 13598267168.

It is an arithmetic number, because the mean of its divisors is an integer number (158530750560).

Almost surely, 2^{21118107706776} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21118107706776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30437904107520).

21118107706776 is an abundant number, since it is smaller than the sum of its proper divisors (39757700508264).

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

21118107706776 is a wasteful number, since it uses less digits than its factorization.

21118107706776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2509 (or 2493 counting only the distinct ones).

The product of its (nonzero) digits is 1382976, while the sum is 54.

Adding to 21118107706776 its reverse (67760770181112), we get a palindrome (88878877887888).

The spelling of 21118107706776 in words is "twenty-one trillion, one hundred eighteen billion, one hundred seven million, seven hundred six thousand, seven hundred seventy-six".