19924739 has 4 divisors (see below), whose sum is σ = 20791056. Its totient is φ = 19058424.

The previous prime is 19924721. The next prime is 19924747. The reversal of 19924739 is 93742991.

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

It is a cyclic number.

It is not a de Polignac number, because 19924739 - 2¹² = 19920643 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19924739.

It is not an unprimeable number, because it can be changed into a prime (19924789) 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, 433124 + ... + 433169.

It is an arithmetic number, because the mean of its divisors is an integer number (5197764).

Almost surely, 2^19924739 is an apocalyptic number.

19924739 is a deficient number, since it is larger than the sum of its proper divisors (866317).

19924739 is an equidigital number, since it uses as much as digits as its factorization.

19924739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 866316.

The product of its digits is 122472, while the sum is 44.

The square root of 19924739 is about 4463.7135884821. The cubic root of 19924739 is about 271.1008507058.

The spelling of 19924739 in words is "nineteen million, nine hundred twenty-four thousand, seven hundred thirty-nine".