861940 has 24 divisors (see below), whose sum is σ = 1838592. Its totient is φ = 339360.

The previous prime is 861937. The next prime is 861941. The reversal of 861940 is 49168.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 861899 and 861908.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1117 + ... + 1723.

It is an arithmetic number, because the mean of its divisors is an integer number (76608).

2⁸⁶¹⁹⁴⁰ is an apocalyptic number.

It is an amenable number.

861940 is an abundant number, since it is smaller than the sum of its proper divisors (976652).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

861940 is a wasteful number, since it uses less digits than its factorization.

861940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 687 (or 685 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 861940 is about 928.4072382312. The cubic root of 861940 is about 95.1683073659.

The spelling of 861940 in words is "eight hundred sixty-one thousand, nine hundred forty".