18002230421 has 4 divisors (see below), whose sum is σ = 20573977632. Its totient is φ = 15430483212.

The previous prime is 18002230417. The next prime is 18002230423. The reversal of 18002230421 is 12403220081.

It is a happy number.

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: 12403220081 = 7 ⋅1771888583.

It is a cyclic number.

It is not a de Polignac number, because 18002230421 - 2² = 18002230417 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 (18002230423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1285873595 + ... + 1285873608.

It is an arithmetic number, because the mean of its divisors is an integer number (5143494408).

Almost surely, 2^18002230421 is an apocalyptic number.

It is an amenable number.

18002230421 is a deficient number, since it is larger than the sum of its proper divisors (2571747211).

18002230421 is an equidigital number, since it uses as much as digits as its factorization.

18002230421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2571747210.

The product of its (nonzero) digits is 768, while the sum is 23.

The spelling of 18002230421 in words is "eighteen billion, two million, two hundred thirty thousand, four hundred twenty-one".