861091611 has 8 divisors (see below), whose sum is σ = 1148476224. Its totient is φ = 573884040.

The previous prime is 861091591. The next prime is 861091631. The reversal of 861091611 is 116190168.

It is an interprime number because it is at equal distance from previous prime (861091591) and next prime (861091631).

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

It is not a de Polignac number, because 861091611 - 2¹⁷ = 860960539 is a prime.

It is not an unprimeable number, because it can be changed into a prime (861091631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32461 + ... + 52686.

It is an arithmetic number, because the mean of its divisors is an integer number (143559528).

Almost surely, 2^861091611 is an apocalyptic number.

861091611 is a deficient number, since it is larger than the sum of its proper divisors (287384613).

861091611 is a wasteful number, since it uses less digits than its factorization.

861091611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88521.

The product of its (nonzero) digits is 2592, while the sum is 33.

The square root of 861091611 is about 29344.3625079844. The cubic root of 861091611 is about 951.3707307669.

The spelling of 861091611 in words is "eight hundred sixty-one million, ninety-one thousand, six hundred eleven".