861011 has 4 divisors (see below), whose sum is σ = 865032. Its totient is φ = 856992.

The previous prime is 861001. The next prime is 861013. The reversal of 861011 is 110168.

It is a happy number.

861011 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 861011 - 2¹⁰ = 859987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861013) 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, 1670 + ... + 2123.

It is an arithmetic number, because the mean of its divisors is an integer number (216258).

2⁸⁶¹⁰¹¹ is an apocalyptic number.

861011 is a deficient number, since it is larger than the sum of its proper divisors (4021).

861011 is a wasteful number, since it uses less digits than its factorization.

861011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4020.

The product of its (nonzero) digits is 48, while the sum is 17.

The square root of 861011 is about 927.9067841114. The cubic root of 861011 is about 95.1341042350.

Adding to 861011 its reverse (110168), we get a palindrome (971179).

The spelling of 861011 in words is "eight hundred sixty-one thousand, eleven".