5406781 has 4 divisors (see below), whose sum is σ = 5412700. Its totient is φ = 5400864.

The previous prime is 5406761. The next prime is 5406809. The reversal of 5406781 is 1876045.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1876045 = 5 ⋅375209.

It can be written as a sum of positive squares in 2 ways, for example, as 416025 + 4990756 = 645^2 + 2234^2 .

It is a cyclic number.

It is not a de Polignac number, because 5406781 - 2⁵ = 5406749 is a prime.

It is a super-2 number, since 2×5406781² = 58466561563922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5406761) 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, 1266 + ... + 3523.

It is an arithmetic number, because the mean of its divisors is an integer number (1353175).

Almost surely, 2^5406781 is an apocalyptic number.

It is an amenable number.

5406781 is a deficient number, since it is larger than the sum of its proper divisors (5919).

5406781 is a wasteful number, since it uses less digits than its factorization.

5406781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5918.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 5406781 is about 2325.2485888610. The cubic root of 5406781 is about 175.5144697393.

The spelling of 5406781 in words is "five million, four hundred six thousand, seven hundred eighty-one".