61689 has 4 divisors (see below), whose sum is σ = 82256. Its totient is φ = 41124.

The previous prime is 61687. The next prime is 61703. The reversal of 61689 is 98616.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 61689 - 2¹ = 61687 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10279 + ... + 10284.

It is an arithmetic number, because the mean of its divisors is an integer number (20564).

2⁶¹⁶⁸⁹ is an apocalyptic number.

It is an amenable number.

61689 is a deficient number, since it is larger than the sum of its proper divisors (20567).

61689 is a wasteful number, since it uses less digits than its factorization.

61689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20566.

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

The square root of 61689 is about 248.3727038142. The cubic root of 61689 is about 39.5126274855.

The spelling of 61689 in words is "sixty-one thousand, six hundred eighty-nine".