18296821 has 4 divisors (see below), whose sum is σ = 18418144. Its totient is φ = 18175500.

The previous prime is 18296813. The next prime is 18296827. The reversal of 18296821 is 12869281.

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.

It is a cyclic number.

It is not a de Polignac number, because 18296821 - 2³ = 18296813 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 (18296827) 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, 60435 + ... + 60736.

It is an arithmetic number, because the mean of its divisors is an integer number (4604536).

Almost surely, 2^18296821 is an apocalyptic number.

It is an amenable number.

18296821 is a deficient number, since it is larger than the sum of its proper divisors (121323).

18296821 is a wasteful number, since it uses less digits than its factorization.

18296821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121322.

The product of its digits is 13824, while the sum is 37.

The square root of 18296821 is about 4277.4783459417. The cubic root of 18296821 is about 263.5068320226.

The spelling of 18296821 in words is "eighteen million, two hundred ninety-six thousand, eight hundred twenty-one".