1897381 has 4 divisors (see below), whose sum is σ = 1929600. Its totient is φ = 1865164.

The previous prime is 1897367. The next prime is 1897403. The reversal of 1897381 is 1837981.

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 1897381 - 2¹⁷ = 1766309 is a prime.

It is a super-2 number, since 2×1897381² = 7200109318322, which contains 22 as substring.

It is a Duffinian number.

1897381 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1897381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1897361) 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, 16021 + ... + 16138.

It is an arithmetic number, because the mean of its divisors is an integer number (482400).

2^1897381 is an apocalyptic number.

It is an amenable number.

1897381 is a deficient number, since it is larger than the sum of its proper divisors (32219).

1897381 is an equidigital number, since it uses as much as digits as its factorization.

1897381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32218.

The product of its digits is 12096, while the sum is 37.

The square root of 1897381 is about 1377.4545364548. The cubic root of 1897381 is about 123.7992981153.

It can be divided in two parts, 1897 and 381, that added together give a triangular number (2278 = T₆₇).

The spelling of 1897381 in words is "one million, eight hundred ninety-seven thousand, three hundred eighty-one".