866149691 has 16 divisors (see below), whose sum is σ = 973594080. Its totient is φ = 763825920.

The previous prime is 866149679. The next prime is 866149693. The reversal of 866149691 is 196941668.

866149691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a de Polignac number, because none of the positive numbers 2^k-866149691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866149693) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43541 + ... + 60233.

It is an arithmetic number, because the mean of its divisors is an integer number (60849630).

Almost surely, 2^866149691 is an apocalyptic number.

866149691 is a deficient number, since it is larger than the sum of its proper divisors (107444389).

866149691 is a wasteful number, since it uses less digits than its factorization.

866149691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16846.

The product of its digits is 559872, while the sum is 50.

The square root of 866149691 is about 29430.4211828509. The cubic root of 866149691 is about 953.2298894095.

The spelling of 866149691 in words is "eight hundred sixty-six million, one hundred forty-nine thousand, six hundred ninety-one".