861923 has 4 divisors (see below), whose sum is σ = 864960. Its totient is φ = 858888.

The previous prime is 861907. The next prime is 861929. The reversal of 861923 is 329168.

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 861923 - 2⁴ = 861907 is a prime.

It is a super-2 number, since 2×861923² = 1485822515858, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (861929) 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 3 ways as a sum of consecutive naturals, for example, 1043 + ... + 1676.

It is an arithmetic number, because the mean of its divisors is an integer number (216240).

2⁸⁶¹⁹²³ is an apocalyptic number.

861923 is a deficient number, since it is larger than the sum of its proper divisors (3037).

861923 is a wasteful number, since it uses less digits than its factorization.

861923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3036.

The product of its digits is 2592, while the sum is 29.

The square root of 861923 is about 928.3980827210. The cubic root of 861923 is about 95.1676816952.

The spelling of 861923 in words is "eight hundred sixty-one thousand, nine hundred twenty-three".