861090 has 16 divisors (see below), whose sum is σ = 2066688. Its totient is φ = 229616.

The previous prime is 861089. The next prime is 861109. The reversal of 861090 is 90168.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 861090.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14322 + ... + 14381.

It is an arithmetic number, because the mean of its divisors is an integer number (129168).

2⁸⁶¹⁰⁹⁰ is an apocalyptic number.

861090 is an abundant number, since it is smaller than the sum of its proper divisors (1205598).

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

861090 is a wasteful number, since it uses less digits than its factorization.

861090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28713.

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 861090 is about 927.9493520662. The cubic root of 861090 is about 95.1370137466.

It can be divided in two parts, 86 and 1090, that added together give a triangular number (1176 = T₄₈).

The spelling of 861090 in words is "eight hundred sixty-one thousand, ninety".