19500139 has 4 divisors (see below), whose sum is σ = 20647224. Its totient is φ = 18353056.

The previous prime is 19500127. The next prime is 19500157. The reversal of 19500139 is 93100591.

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 19500139 - 2¹⁷ = 19369067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19500109) 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, 573517 + ... + 573550.

It is an arithmetic number, because the mean of its divisors is an integer number (5161806).

Almost surely, 2^19500139 is an apocalyptic number.

19500139 is a deficient number, since it is larger than the sum of its proper divisors (1147085).

19500139 is a wasteful number, since it uses less digits than its factorization.

19500139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147084.

The product of its (nonzero) digits is 1215, while the sum is 28.

The square root of 19500139 is about 4415.8961717867. The cubic root of 19500139 is about 269.1612701469.

The spelling of 19500139 in words is "nineteen million, five hundred thousand, one hundred thirty-nine".