19380639 has 4 divisors (see below), whose sum is σ = 25840856. Its totient is φ = 12920424.

The previous prime is 19380623. The next prime is 19380653. The reversal of 19380639 is 93608391.

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

It is not a de Polignac number, because 19380639 - 2⁴ = 19380623 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19380597 and 19380606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19380619) 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, 3230104 + ... + 3230109.

It is an arithmetic number, because the mean of its divisors is an integer number (6460214).

Almost surely, 2^19380639 is an apocalyptic number.

19380639 is a deficient number, since it is larger than the sum of its proper divisors (6460217).

19380639 is an equidigital number, since it uses as much as digits as its factorization.

19380639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6460216.

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 19380639 is about 4402.3447161711. The cubic root of 19380639 is about 268.6103219369.

The spelling of 19380639 in words is "nineteen million, three hundred eighty thousand, six hundred thirty-nine".