1643481 has 24 divisors (see below), whose sum is σ = 2857920. Its totient is φ = 889056.

The previous prime is 1643461. The next prime is 1643491. The reversal of 1643481 is 1843461.

It is not a de Polignac number, because 1643481 - 2¹⁸ = 1381337 is a prime.

It is a super-2 number, since 2×1643481² = 5402059594722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1643431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 511 + ... + 1883.

It is an arithmetic number, because the mean of its divisors is an integer number (119080).

2^1643481 is an apocalyptic number.

It is an amenable number.

1643481 is a deficient number, since it is larger than the sum of its proper divisors (1214439).

1643481 is a wasteful number, since it uses less digits than its factorization.

1643481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1405 (or 1402 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 1643481 is about 1281.9832292195. The cubic root of 1643481 is about 118.0107478480.

The spelling of 1643481 in words is "one million, six hundred forty-three thousand, four hundred eighty-one".