18270397 has 4 divisors (see below), whose sum is σ = 18286560. Its totient is φ = 18254236.

The previous prime is 18270391. The next prime is 18270437. The reversal of 18270397 is 79307281.

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: 79307281 = 2213 ⋅35837.

It is a cyclic number.

It is not a de Polignac number, because 18270397 - 2⁷ = 18270269 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 (18270391) 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, 6247 + ... + 8692.

It is an arithmetic number, because the mean of its divisors is an integer number (4571640).

Almost surely, 2^18270397 is an apocalyptic number.

It is an amenable number.

18270397 is a deficient number, since it is larger than the sum of its proper divisors (16163).

18270397 is a wasteful number, since it uses less digits than its factorization.

18270397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16162.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 18270397 is about 4274.3884942761. The cubic root of 18270397 is about 263.3799200100.

The spelling of 18270397 in words is "eighteen million, two hundred seventy thousand, three hundred ninety-seven".