781481 has 2 divisors, whose sum is σ = 781482. Its totient is φ = 781480.

The previous prime is 781453. The next prime is 781483. The reversal of 781481 is 184187.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 781456 + 25 = 884^2 + 5^2 .

It is an emirp because it is prime and its reverse (184187) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 781481 - 2¹⁰ = 780457 is a prime.

It is a super-2 number, since 2×781481² = 1221425106722, which contains 22 as substring.

Together with 781483, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p₆₂₅₇₉ and since 781481 and 62579 have the same sum of digits, it is a Honaker prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 781481.

It is not a weakly prime, because it can be changed into another prime (781483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 390740 + 390741.

It is an arithmetic number, because the mean of its divisors is an integer number (390741).

2⁷⁸¹⁴⁸¹ is an apocalyptic number.

It is an amenable number.

781481 is a deficient number, since it is larger than the sum of its proper divisors (1).

781481 is an equidigital number, since it uses as much as digits as its factorization.

781481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1792, while the sum is 29.

The square root of 781481 is about 884.0141401584. The cubic root of 781481 is about 92.1098640251.

Subtracting from 781481 its product of digits (1792), we obtain a square (779689 = 883²).

The spelling of 781481 in words is "seven hundred eighty-one thousand, four hundred eighty-one".