19428739 has 16 divisors (see below), whose sum is σ = 22674816. Its totient is φ = 16451200.

The previous prime is 19428691. The next prime is 19428743. The reversal of 19428739 is 93782491.

It is a cyclic number.

It is not a de Polignac number, because 19428739 - 2²³ = 11040131 is a prime.

It is a Duffinian number.

19428739 is a modest number, since divided by 8739 gives 1942 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 19428695 and 19428704.

It is not an unprimeable number, because it can be changed into a prime (19428749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19524 + ... + 20494.

It is an arithmetic number, because the mean of its divisors is an integer number (1417176).

Almost surely, 2^19428739 is an apocalyptic number.

19428739 is a deficient number, since it is larger than the sum of its proper divisors (3246077).

19428739 is a wasteful number, since it uses less digits than its factorization.

19428739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1106.

The product of its digits is 108864, while the sum is 43.

The square root of 19428739 is about 4407.8043286879. The cubic root of 19428739 is about 268.8323559392.

The spelling of 19428739 in words is "nineteen million, four hundred twenty-eight thousand, seven hundred thirty-nine".