1897890 has 32 divisors (see below), whose sum is σ = 4669056. Its totient is φ = 493440.

The previous prime is 1897871. The next prime is 1897939. The reversal of 1897890 is 987981.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 459 + ... + 2001.

It is an arithmetic number, because the mean of its divisors is an integer number (145908).

2^1897890 is an apocalyptic number.

1897890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1897890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2334528).

1897890 is an abundant number, since it is smaller than the sum of its proper divisors (2771166).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1897890 is a wasteful number, since it uses less digits than its factorization.

1897890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1594.

The product of its (nonzero) digits is 36288, while the sum is 42.

The square root of 1897890 is about 1377.6392851541. The cubic root of 1897890 is about 123.8103674452.

Subtracting from 1897890 its reverse (987981), we obtain a palindrome (909909).

The spelling of 1897890 in words is "one million, eight hundred ninety-seven thousand, eight hundred ninety".