609861 has 16 divisors (see below), whose sum is σ = 941184. Its totient is φ = 344064.

The previous prime is 609859. The next prime is 609877. The reversal of 609861 is 168906.

It is not a de Polignac number, because 609861 - 2¹ = 609859 is a prime.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 609861.

It is not an unprimeable number, because it can be changed into a prime (609821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2245 + ... + 2501.

It is an arithmetic number, because the mean of its divisors is an integer number (58824).

2⁶⁰⁹⁸⁶¹ is an apocalyptic number.

It is an amenable number.

609861 is a deficient number, since it is larger than the sum of its proper divisors (331323).

609861 is a wasteful number, since it uses less digits than its factorization.

609861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 380.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 609861 is about 780.9359768893. The cubic root of 609861 is about 84.8028185992.

The spelling of 609861 in words is "six hundred nine thousand, eight hundred sixty-one".