545531 has 4 divisors (see below), whose sum is σ = 623472. Its totient is φ = 467592.

The previous prime is 545527. The next prime is 545533. The reversal of 545531 is 135545.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 135545 = 5 ⋅27109.

It is a cyclic number.

It is not a de Polignac number, because 545531 - 2² = 545527 is a prime.

It is a super-2 number, since 2×545531² = 595208143922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 545497 and 545506.

It is not an unprimeable number, because it can be changed into a prime (545533) 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 3 ways as a sum of consecutive naturals, for example, 38960 + ... + 38973.

It is an arithmetic number, because the mean of its divisors is an integer number (155868).

2⁵⁴⁵⁵³¹ is an apocalyptic number.

545531 is a deficient number, since it is larger than the sum of its proper divisors (77941).

545531 is an equidigital number, since it uses as much as digits as its factorization.

545531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77940.

The product of its digits is 1500, while the sum is 23.

The square root of 545531 is about 738.6007040343. The cubic root of 545531 is about 81.7096113622.

The spelling of 545531 in words is "five hundred forty-five thousand, five hundred thirty-one".