866761025850061 has 8 divisors (see below), whose sum is σ = 896650228968120. Its totient is φ = 836871882190848.

The previous prime is 866761025850019. The next prime is 866761025850067. The reversal of 866761025850061 is 160058520167668.

It can be written as a sum of positive squares in 4 ways, for example, as 133636628737161 + 733124397112900 = 11560131^2 + 27076270^2 .

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 866761025850061 - 2¹⁵ = 866761025817293 is a prime.

It is a super-2 number, since 2×866761025850061² (a number of 31 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 (866761025850067) 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, 15870085 + ... + 44557621.

It is an arithmetic number, because the mean of its divisors is an integer number (112081278621015).

Almost surely, 2^{866761025850061} is an apocalyptic number.

It is an amenable number.

866761025850061 is a deficient number, since it is larger than the sum of its proper divisors (29889203118059).

866761025850061 is a wasteful number, since it uses less digits than its factorization.

866761025850061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29729423.

The product of its (nonzero) digits is 29030400, while the sum is 61.

The spelling of 866761025850061 in words is "eight hundred sixty-six trillion, seven hundred sixty-one billion, twenty-five million, eight hundred fifty thousand, sixty-one".