861623 has 8 divisors (see below), whose sum is σ = 997248. Its totient is φ = 729144.

The previous prime is 861617. The next prime is 861647. The reversal of 861623 is 326168.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 861623 - 2⁶ = 861559 is a prime.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 861592 and 861601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861613) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161 + ... + 1322.

It is an arithmetic number, because the mean of its divisors is an integer number (124656).

2⁸⁶¹⁶²³ is an apocalyptic number.

861623 is a gapful number since it is divisible by the number (83) formed by its first and last digit.

861623 is a deficient number, since it is larger than the sum of its proper divisors (135625).

861623 is a wasteful number, since it uses less digits than its factorization.

861623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1573.

The product of its digits is 1728, while the sum is 26.

The square root of 861623 is about 928.2365000365. The cubic root of 861623 is about 95.1566390933.

The spelling of 861623 in words is "eight hundred sixty-one thousand, six hundred twenty-three".