1981255 has 8 divisors (see below), whose sum is σ = 2411424. Its totient is φ = 1562400.

The previous prime is 1981247. The next prime is 1981267. The reversal of 1981255 is 5521891.

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

It is not a de Polignac number, because 1981255 - 2³ = 1981247 is a prime.

It is a super-3 number, since 3×1981255³ = 23331484990875469125, which contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2436 + ... + 3145.

It is an arithmetic number, because the mean of its divisors is an integer number (301428).

2^1981255 is an apocalyptic number.

1981255 is a deficient number, since it is larger than the sum of its proper divisors (430169).

1981255 is an equidigital number, since it uses as much as digits as its factorization.

1981255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5657.

The product of its digits is 3600, while the sum is 31.

The square root of 1981255 is about 1407.5706021369. The cubic root of 1981255 is about 125.5972484758.

The spelling of 1981255 in words is "one million, nine hundred eighty-one thousand, two hundred fifty-five".