19655 has 4 divisors (see below), whose sum is σ = 23592. Its totient is φ = 15720.

The previous prime is 19609. The next prime is 19661. The reversal of 19655 is 55691.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 19655 - 2¹² = 15559 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1961 + ... + 1970.

It is an arithmetic number, because the mean of its divisors is an integer number (5898).

2¹⁹⁶⁵⁵ is an apocalyptic number.

19655 is a deficient number, since it is larger than the sum of its proper divisors (3937).

19655 is an equidigital number, since it uses as much as digits as its factorization.

19655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3936.

The product of its digits is 1350, while the sum is 26.

The square root of 19655 is about 140.1962909638. The cubic root of 19655 is about 26.9871909979.

The spelling of 19655 in words is "nineteen thousand, six hundred fifty-five".