540391 has 2 divisors, whose sum is σ = 540392. Its totient is φ = 540390.

The previous prime is 540389. The next prime is 540433. The reversal of 540391 is 193045.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 540391 - 2¹ = 540389 is a prime.

Together with 540389, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (540301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 270195 + 270196.

It is an arithmetic number, because the mean of its divisors is an integer number (270196).

2⁵⁴⁰³⁹¹ is an apocalyptic number.

540391 is a deficient number, since it is larger than the sum of its proper divisors (1).

540391 is an equidigital number, since it uses as much as digits as its factorization.

540391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 540391 is about 735.1129164965. The cubic root of 540391 is about 81.4521781502.

The spelling of 540391 in words is "five hundred forty thousand, three hundred ninety-one".