1851481 has 4 divisors (see below), whose sum is σ = 1873872. Its totient is φ = 1829092.

The previous prime is 1851469. The next prime is 1851491. The reversal of 1851481 is 1841581.

It is the 556-th star number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1841581 = 7 ⋅263083.

It is a cyclic number.

It is not a de Polignac number, because 1851481 - 2⁹ = 1850969 is a prime.

It is a super-2 number, since 2×1851481² = 6855963786722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1851401) 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, 11071 + ... + 11236.

It is an arithmetic number, because the mean of its divisors is an integer number (468468).

2^1851481 is an apocalyptic number.

It is an amenable number.

1851481 is a deficient number, since it is larger than the sum of its proper divisors (22391).

1851481 is an equidigital number, since it uses as much as digits as its factorization.

1851481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22390.

The product of its digits is 1280, while the sum is 28.

The square root of 1851481 is about 1360.6913683859. The cubic root of 1851481 is about 122.7928520280.

It can be divided in two parts, 1851 and 481, that added together give a palindrome (2332).

The spelling of 1851481 in words is "one million, eight hundred fifty-one thousand, four hundred eighty-one".