19944247 has 4 divisors (see below), whose sum is σ = 21117456. Its totient is φ = 18771040.

The previous prime is 19944241. The next prime is 19944251. The reversal of 19944247 is 74244991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74244991 = 61 ⋅1217131.

It is a cyclic number.

It is not a de Polignac number, because 19944247 - 2¹¹ = 19942199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19944241) 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, 586579 + ... + 586612.

It is an arithmetic number, because the mean of its divisors is an integer number (5279364).

Almost surely, 2^19944247 is an apocalyptic number.

19944247 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

19944247 is a deficient number, since it is larger than the sum of its proper divisors (1173209).

19944247 is a wasteful number, since it uses less digits than its factorization.

19944247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1173208.

The product of its digits is 72576, while the sum is 40.

The square root of 19944247 is about 4465.8982299197. The cubic root of 19944247 is about 271.1892987122.

It can be divided in two parts, 1994 and 4247, that added together give a square (6241 = 79²).

The spelling of 19944247 in words is "nineteen million, nine hundred forty-four thousand, two hundred forty-seven".