1881281 has 4 divisors (see below), whose sum is σ = 1885632. Its totient is φ = 1876932.

The previous prime is 1881277. The next prime is 1881289. The reversal of 1881281 is 1821881.

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: 1821881 = 827 ⋅2203.

It is a cyclic number.

It is not a de Polignac number, because 1881281 - 2² = 1881277 is a prime.

It is a super-3 number, since 3×1881281³ = 19974791868966333123, which contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1881289) 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, 1445 + ... + 2418.

It is an arithmetic number, because the mean of its divisors is an integer number (471408).

2^1881281 is an apocalyptic number.

It is an amenable number.

1881281 is a deficient number, since it is larger than the sum of its proper divisors (4351).

1881281 is an equidigital number, since it uses as much as digits as its factorization.

1881281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4350.

The product of its digits is 1024, while the sum is 29.

The square root of 1881281 is about 1371.5979731685. The cubic root of 1881281 is about 123.4481416131.

The spelling of 1881281 in words is "one million, eight hundred eighty-one thousand, two hundred eighty-one".