1981427 has 16 divisors (see below), whose sum is σ = 2445312. Its totient is φ = 1568160.

The previous prime is 1981417. The next prime is 1981429. The reversal of 1981427 is 7241891.

It is a cyclic number.

It is not a de Polignac number, because 1981427 - 2¹⁶ = 1915891 is a prime.

It is a super-3 number, since 3×1981427³ = 23337561993300304449, which contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1981393 and 1981402.

It is not an unprimeable number, because it can be changed into a prime (1981429) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4793 + ... + 5189.

It is an arithmetic number, because the mean of its divisors is an integer number (152832).

2^1981427 is an apocalyptic number.

1981427 is a deficient number, since it is larger than the sum of its proper divisors (463885).

1981427 is a wasteful number, since it uses less digits than its factorization.

1981427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458.

The product of its digits is 4032, while the sum is 32.

The square root of 1981427 is about 1407.6316989895. The cubic root of 1981427 is about 125.6008828897.

The spelling of 1981427 in words is "one million, nine hundred eighty-one thousand, four hundred twenty-seven".