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1890 = 23357
BaseRepresentation
bin11101100010
32121000
4131202
530030
612430
75340
oct3542
92530
101890
111469
121116
13b25
14990
15860
hex762

1890 has 32 divisors (see below), whose sum is σ = 5760. Its totient is φ = 432.

The previous prime is 1889. The next prime is 1901. The reversal of 1890 is 981.

1890 divided by its sum of digits (18) gives a triangular number (105 = T14).

Subtracting from 1890 its reverse (981), we obtain a palindrome (909).

It is a Harshad number since it is a multiple of its sum of digits (18).

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

It is a plaindrome in base 11 and base 12.

It is a nialpdrome in base 14, base 15 and base 16.

It is a congruent number.

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, 267 + ... + 273.

It is an arithmetic number, because the mean of its divisors is an integer number (180).

1890 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 1890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2880).

1890 is an abundant number, since it is smaller than the sum of its proper divisors (3870).

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

1890 is a wasteful number, since it uses less digits than its factorization.

1890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23 (or 17 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 1890 is about 43.4741302386. The cubic root of 1890 is about 12.3638558994.

The spelling of 1890 in words is "one thousand, eight hundred ninety".