1781481 has 16 divisors (see below), whose sum is σ = 2709504. Its totient is φ = 1031424.

The previous prime is 1781467. The next prime is 1781503. The reversal of 1781481 is 1841871.

It is not a de Polignac number, because 1781481 - 2⁵ = 1781449 is a prime.

It is a super-2 number, since 2×1781481² = 6347349106722, which contains 22 as substring.

1781481 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1781581) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 681 + ... + 2006.

It is an arithmetic number, because the mean of its divisors is an integer number (169344).

2^1781481 is an apocalyptic number.

It is an amenable number.

1781481 is a deficient number, since it is larger than the sum of its proper divisors (928023).

1781481 is a wasteful number, since it uses less digits than its factorization.

1781481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2720.

The product of its digits is 1792, while the sum is 30.

The square root of 1781481 is about 1334.7213192274. The cubic root of 1781481 is about 121.2254295344.

The spelling of 1781481 in words is "one million, seven hundred eighty-one thousand, four hundred eighty-one".