18915413 has 4 divisors (see below), whose sum is σ = 20635008. Its totient is φ = 17195820.

The previous prime is 18915397. The next prime is 18915419. The reversal of 18915413 is 31451981.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 31451981 = 11 ⋅2859271.

It is a cyclic number.

It is not a de Polignac number, because 18915413 - 2⁴ = 18915397 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18915413.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18915419) 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, 859781 + ... + 859802.

It is an arithmetic number, because the mean of its divisors is an integer number (5158752).

Almost surely, 2^18915413 is an apocalyptic number.

It is an amenable number.

18915413 is a deficient number, since it is larger than the sum of its proper divisors (1719595).

18915413 is a wasteful number, since it uses less digits than its factorization.

18915413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1719594.

The product of its digits is 4320, while the sum is 32.

The square root of 18915413 is about 4349.1853260122. The cubic root of 18915413 is about 266.4435896547.

The spelling of 18915413 in words is "eighteen million, nine hundred fifteen thousand, four hundred thirteen".