1966049861281 has 27 divisors (see below), whose sum is σ = 2215736308569. Its totient is φ = 1743164068800.

The previous prime is 1966049861267. The next prime is 1966049861299. The reversal of 1966049861281 is 1821689406691.

The square root of 1966049861281 is 1402159.

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

It can be written as a sum of positive squares in 4 ways, for example, as 1234785441681 + 731264419600 = 1111209^2 + 855140^2 .

It is not a de Polignac number, because 1966049861281 - 2⁵ = 1966049861249 is a prime.

It is a super-2 number, since 2×1966049861281² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1966049861381) 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 26 ways as a sum of consecutive naturals, for example, 632372155 + ... + 632375263.

Almost surely, 2^{1966049861281} is an apocalyptic number.

1966049861281 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1966049861281 is the 1402159-th square number.

1966049861281 is the 701080-th centered octagonal number.

It is an amenable number.

1966049861281 is a deficient number, since it is larger than the sum of its proper divisors (249686447288).

1966049861281 is an frugal number, since it uses more digits than its factorization.

1966049861281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6322 (or 3161 counting only the distinct ones).

The product of its (nonzero) digits is 8957952, while the sum is 61.

The spelling of 1966049861281 in words is "one trillion, nine hundred sixty-six billion, forty-nine million, eight hundred sixty-one thousand, two hundred eighty-one".