1898381 has 4 divisors (see below), whose sum is σ = 1929564. Its totient is φ = 1867200.

The previous prime is 1898371. The next prime is 1898383. The reversal of 1898381 is 1838981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1838981 = 43 ⋅42767.

It can be written as a sum of positive squares in 2 ways, for example, as 434281 + 1464100 = 659^2 + 1210^2 .

It is a cyclic number.

It is not a de Polignac number, because 1898381 - 2⁶ = 1898317 is a prime.

It is a super-2 number, since 2×1898381² = 7207700842322, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1898383) 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, 15500 + ... + 15621.

It is an arithmetic number, because the mean of its divisors is an integer number (482391).

2^1898381 is an apocalyptic number.

It is an amenable number.

1898381 is a deficient number, since it is larger than the sum of its proper divisors (31183).

1898381 is an equidigital number, since it uses as much as digits as its factorization.

1898381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31182.

The product of its digits is 13824, while the sum is 38.

The square root of 1898381 is about 1377.8174770266. The cubic root of 1898381 is about 123.8210434501.

The spelling of 1898381 in words is "one million, eight hundred ninety-eight thousand, three hundred eighty-one".