3261000610781 has 4 divisors (see below), whose sum is σ = 3261240810012. Its totient is φ = 3260760411552.

The previous prime is 3261000610687. The next prime is 3261000610807. The reversal of 3261000610781 is 1870160001623.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2678816350681 + 582184260100 = 1636709^2 + 763010^2 .

It is a cyclic number.

It is not a de Polignac number, because 3261000610781 - 2¹⁸ = 3261000348637 is a prime.

It is a super-2 number, since 2×3261000610781² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3261000630781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120079250 + ... + 120106403.

It is an arithmetic number, because the mean of its divisors is an integer number (815310202503).

Almost surely, 2^{3261000610781} is an apocalyptic number.

It is an amenable number.

3261000610781 is a deficient number, since it is larger than the sum of its proper divisors (240199231).

3261000610781 is a wasteful number, since it uses less digits than its factorization.

3261000610781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240199230.

The product of its (nonzero) digits is 12096, while the sum is 35.

The spelling of 3261000610781 in words is "three trillion, two hundred sixty-one billion, six hundred ten thousand, seven hundred eighty-one".