19985743 has 4 divisors (see below), whose sum is σ = 20056648. Its totient is φ = 19914840.

The previous prime is 19985741. The next prime is 19985747. The reversal of 19985743 is 34758991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34758991 = 47 ⋅739553.

It is a cyclic number.

It is not a de Polignac number, because 19985743 - 2¹ = 19985741 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19985693 and 19985702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19985741) 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, 35028 + ... + 35593.

It is an arithmetic number, because the mean of its divisors is an integer number (5014162).

Almost surely, 2^19985743 is an apocalyptic number.

19985743 is a deficient number, since it is larger than the sum of its proper divisors (70905).

19985743 is an equidigital number, since it uses as much as digits as its factorization.

19985743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70904.

The product of its digits is 272160, while the sum is 46.

The square root of 19985743 is about 4470.5416897732. The cubic root of 19985743 is about 271.3772472408.

The spelling of 19985743 in words is "nineteen million, nine hundred eighty-five thousand, seven hundred forty-three".