19450139 has 4 divisors (see below), whose sum is σ = 19632024. Its totient is φ = 19268256.

The previous prime is 19450121. The next prime is 19450153. The reversal of 19450139 is 93105491.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93105491 = 19 ⋅4900289.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19450139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19450199) 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 3 ways as a sum of consecutive naturals, for example, 90782 + ... + 90995.

It is an arithmetic number, because the mean of its divisors is an integer number (4908006).

Almost surely, 2^19450139 is an apocalyptic number.

19450139 is a deficient number, since it is larger than the sum of its proper divisors (181885).

19450139 is a wasteful number, since it uses less digits than its factorization.

19450139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181884.

The product of its (nonzero) digits is 4860, while the sum is 32.

The square root of 19450139 is about 4410.2311730793. The cubic root of 19450139 is about 268.9310225154.

The spelling of 19450139 in words is "nineteen million, four hundred fifty thousand, one hundred thirty-nine".