18470381 has 4 divisors (see below), whose sum is σ = 19556892. Its totient is φ = 17383872.

The previous prime is 18470371. The next prime is 18470393. The reversal of 18470381 is 18307481.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18307481 = 149 ⋅122869.

It can be written as a sum of positive squares in 2 ways, for example, as 17147881 + 1322500 = 4141^2 + 1150^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18470381 is a prime.

It is a super-2 number, since 2×18470381² = 682309948570322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18470321) 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, 543230 + ... + 543263.

It is an arithmetic number, because the mean of its divisors is an integer number (4889223).

Almost surely, 2^18470381 is an apocalyptic number.

It is an amenable number.

18470381 is a deficient number, since it is larger than the sum of its proper divisors (1086511).

18470381 is a wasteful number, since it uses less digits than its factorization.

18470381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086510.

The product of its (nonzero) digits is 5376, while the sum is 32.

The square root of 18470381 is about 4297.7181154655. The cubic root of 18470381 is about 264.3374024334.

The spelling of 18470381 in words is "eighteen million, four hundred seventy thousand, three hundred eighty-one".