109287976819921 has 3 divisors (see below), whose sum is σ = 109287987274011. Its totient is φ = 109287966365832.

The previous prime is 109287976819873. The next prime is 109287976819933. The reversal of 109287976819921 is 129918679782901.

The square root of 109287976819921 is 10454089.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 98478611002321 + 10809365817600 = 9923639^2 + 3287760^2 .

It is not a de Polignac number, because 109287976819921 - 2⁹ = 109287976819409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (109287976819321) 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 2 ways as a sum of consecutive naturals, for example, 5227045 + ... + 15681133.

It is an arithmetic number, because the mean of its divisors is an integer number (36429329091337).

Almost surely, 2^{109287976819921} is an apocalyptic number.

109287976819921 is the 10454089-th square number.

109287976819921 is the 5227045-th centered octagonal number.

It is an amenable number.

109287976819921 is a deficient number, since it is larger than the sum of its proper divisors (10454090).

109287976819921 is an frugal number, since it uses more digits than its factorization.

109287976819921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20908178 (or 10454089 counting only the distinct ones).

The product of its (nonzero) digits is 493807104, while the sum is 79.

The spelling of 109287976819921 in words is "one hundred nine trillion, two hundred eighty-seven billion, nine hundred seventy-six million, eight hundred nineteen thousand, nine hundred twenty-one".