19139747 has 4 divisors (see below), whose sum is σ = 20879736. Its totient is φ = 17399760.

The previous prime is 19139737. The next prime is 19139801. The reversal of 19139747 is 74793191.

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 19139747 - 2¹² = 19135651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19139737) 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, 869978 + ... + 869999.

It is an arithmetic number, because the mean of its divisors is an integer number (5219934).

Almost surely, 2^19139747 is an apocalyptic number.

19139747 is a deficient number, since it is larger than the sum of its proper divisors (1739989).

19139747 is a wasteful number, since it uses less digits than its factorization.

19139747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1739988.

The product of its digits is 47628, while the sum is 41.

The square root of 19139747 is about 4374.8996559921. The cubic root of 19139747 is about 267.4927799606.

The spelling of 19139747 in words is "nineteen million, one hundred thirty-nine thousand, seven hundred forty-seven".