19742 has 4 divisors (see below), whose sum is σ = 29616. Its totient is φ = 9870.

The previous prime is 19739. The next prime is 19751. The reversal of 19742 is 24791.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24791 = 13 ⋅1907.

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 19742.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4934 + ... + 4937.

It is an arithmetic number, because the mean of its divisors is an integer number (7404).

2¹⁹⁷⁴² is an apocalyptic number.

19742 is a deficient number, since it is larger than the sum of its proper divisors (9874).

19742 is an equidigital number, since it uses as much as digits as its factorization.

19742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9873.

The product of its digits is 504, while the sum is 23.

The square root of 19742 is about 140.5062276200. The cubic root of 19742 is about 27.0269506845.

The spelling of 19742 in words is "nineteen thousand, seven hundred forty-two".