1820890 has 8 divisors (see below), whose sum is σ = 3277620. Its totient is φ = 728352.

The previous prime is 1820869. The next prime is 1820891. The reversal of 1820890 is 980281.

It can be written as a sum of positive squares in 2 ways, for example, as 1819801 + 1089 = 1349^2 + 33^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (1820891) 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, 91035 + ... + 91054.

2^1820890 is an apocalyptic number.

1820890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1820890 is a deficient number, since it is larger than the sum of its proper divisors (1456730).

1820890 is a wasteful number, since it uses less digits than its factorization.

1820890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182096.

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 1820890 is about 1349.4035719532. The cubic root of 1820890 is about 122.1128133239.

The spelling of 1820890 in words is "one million, eight hundred twenty thousand, eight hundred ninety".