3261784093681 has 3 divisors (see below), whose sum is σ = 3261785899723. Its totient is φ = 3261782287640.

The previous prime is 3261784093679. The next prime is 3261784093697. The reversal of 3261784093681 is 1863904871623.

The square root of 3261784093681 is 1806041.

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., 2543358333681 + 718425760000 = 1594791^2 + 847600^2 .

It is not a de Polignac number, because 3261784093681 - 2¹ = 3261784093679 is a prime.

It is a super-2 number, since 2×3261784093681² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3261784093651) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 903021 + ... + 2709061.

Almost surely, 2^{3261784093681} is an apocalyptic number.

3261784093681 is the 1806041-st square number.

3261784093681 is the 903021-st centered octagonal number.

It is an amenable number.

3261784093681 is a deficient number, since it is larger than the sum of its proper divisors (1806042).

3261784093681 is an frugal number, since it uses more digits than its factorization.

3261784093681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3612082 (or 1806041 counting only the distinct ones).

The product of its (nonzero) digits is 10450944, while the sum is 58.

The spelling of 3261784093681 in words is "three trillion, two hundred sixty-one billion, seven hundred eighty-four million, ninety-three thousand, six hundred eighty-one".