109766978721 has 9 divisors (see below), whose sum is σ = 158553738291. Its totient is φ = 73177323192.

The previous prime is 109766978719. The next prime is 109766978723. The reversal of 109766978721 is 127879667901.

The square root of 109766978721 is 331311.

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

It is an interprime number because it is at equal distance from previous prime (109766978719) and next prime (109766978723).

It can be written as a sum of positive squares in only one way, i.e., 82331694225 + 27435284496 = 286935^2 + 165636^2 .

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 109766978721 - 2¹ = 109766978719 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (109766978723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 938715 + ... + 1049151.

Almost surely, 2^109766978721 is an apocalyptic number.

109766978721 is the 331311-st square number.

109766978721 is the 165656-th centered octagonal number.

It is an amenable number.

109766978721 is a deficient number, since it is larger than the sum of its proper divisors (48786759570).

109766978721 is an frugal number, since it uses more digits than its factorization.

109766978721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220880 (or 110440 counting only the distinct ones).

The product of its (nonzero) digits is 16003008, while the sum is 63.

The spelling of 109766978721 in words is "one hundred nine billion, seven hundred sixty-six million, nine hundred seventy-eight thousand, seven hundred twenty-one".