19121019 has 4 divisors (see below), whose sum is σ = 25494696. Its totient is φ = 12747344.

The previous prime is 19120987. The next prime is 19121029. The reversal of 19121019 is 91012191.

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 19121019 - 2⁵ = 19120987 is a prime.

It is a super-2 number, since 2×19121019² = 731226735196722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 19121019.

It is not an unprimeable number, because it can be changed into a prime (19121029) 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, 3186834 + ... + 3186839.

It is an arithmetic number, because the mean of its divisors is an integer number (6373674).

Almost surely, 2^19121019 is an apocalyptic number.

19121019 is a deficient number, since it is larger than the sum of its proper divisors (6373677).

19121019 is an equidigital number, since it uses as much as digits as its factorization.

19121019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6373676.

The product of its (nonzero) digits is 162, while the sum is 24.

The square root of 19121019 is about 4372.7587402005. The cubic root of 19121019 is about 267.4055053897.

The spelling of 19121019 in words is "nineteen million, one hundred twenty-one thousand, nineteen".