1227981 has 4 divisors (see below), whose sum is σ = 1637312. Its totient is φ = 818652.

The previous prime is 1227979. The next prime is 1227983. The reversal of 1227981 is 1897221.

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.

It is an interprime number because it is at equal distance from previous prime (1227979) and next prime (1227983).

It is not a de Polignac number, because 1227981 - 2¹ = 1227979 is a prime.

It is a super-2 number, since 2×1227981² = 3015874672722, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1227983) 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, 204661 + ... + 204666.

It is an arithmetic number, because the mean of its divisors is an integer number (409328).

2^1227981 is an apocalyptic number.

It is an amenable number.

1227981 is a deficient number, since it is larger than the sum of its proper divisors (409331).

1227981 is an equidigital number, since it uses as much as digits as its factorization.

1227981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409330.

The product of its digits is 2016, while the sum is 30.

The square root of 1227981 is about 1108.1430413083. The cubic root of 1227981 is about 107.0854704750.

The spelling of 1227981 in words is "one million, two hundred twenty-seven thousand, nine hundred eighty-one".