19142309 has 4 divisors (see below), whose sum is σ = 19213740. Its totient is φ = 19070880.

The previous prime is 19142303. The next prime is 19142311. The reversal of 19142309 is 90324191.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 90324191 = 461 ⋅195931.

It can be written as a sum of positive squares in 2 ways, for example, as 6646084 + 12496225 = 2578^2 + 3535^2 .

It is a cyclic number.

It is not a de Polignac number, because 19142309 - 2²⁴ = 2365093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19142303) 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, 35312 + ... + 35849.

It is an arithmetic number, because the mean of its divisors is an integer number (4803435).

Almost surely, 2^19142309 is an apocalyptic number.

It is an amenable number.

19142309 is a deficient number, since it is larger than the sum of its proper divisors (71431).

19142309 is an equidigital number, since it uses as much as digits as its factorization.

19142309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71430.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 19142309 is about 4375.1924529099. The cubic root of 19142309 is about 267.5047147392.

The spelling of 19142309 in words is "nineteen million, one hundred forty-two thousand, three hundred nine".