19148909 has 4 divisors (see below), whose sum is σ = 20621916. Its totient is φ = 17675904.

The previous prime is 19148897. The next prime is 19148911. The reversal of 19148909 is 90984191.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1060900 + 18088009 = 1030^2 + 4253^2 .

It is a cyclic number.

It is not a de Polignac number, because 19148909 - 2⁸ = 19148653 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 (19148929) 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, 736484 + ... + 736509.

It is an arithmetic number, because the mean of its divisors is an integer number (5155479).

Almost surely, 2^19148909 is an apocalyptic number.

It is an amenable number.

19148909 is a deficient number, since it is larger than the sum of its proper divisors (1473007).

19148909 is a wasteful number, since it uses less digits than its factorization.

19148909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1473006.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 19148909 is about 4375.9466404425. The cubic root of 19148909 is about 267.5354551660.

The spelling of 19148909 in words is "nineteen million, one hundred forty-eight thousand, nine hundred nine".