261872890817 has 8 divisors (see below), whose sum is σ = 270335950080. Its totient is φ = 253410803280.

The previous prime is 261872890753. The next prime is 261872890861. The reversal of 261872890817 is 718098278162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261872890817 - 2⁶ = 261872890753 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261872890897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 325943 + ... + 793715.

It is an arithmetic number, because the mean of its divisors is an integer number (33791993760).

Almost surely, 2^261872890817 is an apocalyptic number.

It is an amenable number.

261872890817 is a deficient number, since it is larger than the sum of its proper divisors (8463059263).

261872890817 is a wasteful number, since it uses less digits than its factorization.

261872890817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485863.

The product of its (nonzero) digits is 5419008, while the sum is 59.

The spelling of 261872890817 in words is "two hundred sixty-one billion, eight hundred seventy-two million, eight hundred ninety thousand, eight hundred seventeen".