1279819326681 has 45 divisors (see below), whose sum is σ = 2224088052879. Its totient is φ = 731284603056.

The previous prime is 1279819326631. The next prime is 1279819326697. The reversal of 1279819326681 is 1866239189721.

The square root of 1279819326681 is 1131291.

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

1279819326681 is a `hidden beast` number, since 1 + 27 + 98 + 193 + 266 + 81 = 666.

It can be written as a sum of positive squares in only one way, i.e., 1279534257225 + 285069456 = 1131165^2 + 16884^2 .

It is not a de Polignac number, because 1279819326681 - 2⁹ = 1279819326169 is a prime.

It is a super-2 number, since 2×1279819326681² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (1279819326601) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 71262355 + ... + 71280311.

Almost surely, 2^{1279819326681} is an apocalyptic number.

1279819326681 is the 1131291-st square number.

1279819326681 is the 565646-th centered octagonal number.

It is an amenable number.

1279819326681 is a deficient number, since it is larger than the sum of its proper divisors (944268726198).

1279819326681 is an frugal number, since it uses more digits than its factorization.

1279819326681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35940 (or 17967 counting only the distinct ones).

The product of its digits is 15676416, while the sum is 63.

The spelling of 1279819326681 in words is "one trillion, two hundred seventy-nine billion, eight hundred nineteen million, three hundred twenty-six thousand, six hundred eighty-one".