1820538 has 12 divisors (see below), whose sum is σ = 3944538. Its totient is φ = 606840.

The previous prime is 1820527. The next prime is 1820549. The reversal of 1820538 is 8350281.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1820527) and next prime (1820549).

It can be written as a sum of positive squares in only one way, i.e., 1306449 + 514089 = 1143^2 + 717^2 .

It is a plaindrome in base 14.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 50553 + ... + 50588.

2^1820538 is an apocalyptic number.

1820538 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1820538 is an abundant number, since it is smaller than the sum of its proper divisors (2124000).

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

1820538 is a wasteful number, since it uses less digits than its factorization.

1820538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101149 (or 101146 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 1820538 is about 1349.2731376560. The cubic root of 1820538 is about 122.1049441902.

The spelling of 1820538 in words is "one million, eight hundred twenty thousand, five hundred thirty-eight".