18872215 has 4 divisors (see below), whose sum is σ = 22646664. Its totient is φ = 15097768.

The previous prime is 18872209. The next prime is 18872219. The reversal of 18872215 is 51227881.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51227881 = 1237 ⋅41413.

It is a cyclic number.

It is not a de Polignac number, because 18872215 - 2¹³ = 18864023 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 (18872219) 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, 1887217 + ... + 1887226.

It is an arithmetic number, because the mean of its divisors is an integer number (5661666).

Almost surely, 2^18872215 is an apocalyptic number.

18872215 is a deficient number, since it is larger than the sum of its proper divisors (3774449).

18872215 is an equidigital number, since it uses as much as digits as its factorization.

18872215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3774448.

The product of its digits is 8960, while the sum is 34.

The square root of 18872215 is about 4344.2162699387. The cubic root of 18872215 is about 266.2406052215.

The spelling of 18872215 in words is "eighteen million, eight hundred seventy-two thousand, two hundred fifteen".