540621 has 8 divisors (see below), whose sum is σ = 800960. Its totient is φ = 360396.

The previous prime is 540619. The next prime is 540629. The reversal of 540621 is 126045.

It is a happy number.

540621 is a `hidden beast` number, since 5 + 40 + 621 = 666.

It is not a de Polignac number, because 540621 - 2¹ = 540619 is a prime.

It is a super-3 number, since 3×540621³ = 474023627333709183, which contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 540594 and 540603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (540629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9985 + ... + 10038.

It is an arithmetic number, because the mean of its divisors is an integer number (100120).

2⁵⁴⁰⁶²¹ is an apocalyptic number.

It is an amenable number.

540621 is a deficient number, since it is larger than the sum of its proper divisors (260339).

540621 is a wasteful number, since it uses less digits than its factorization.

540621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20032 (or 20026 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 540621 is about 735.2693384060. The cubic root of 540621 is about 81.4637323420.

Adding to 540621 its reverse (126045), we get a palindrome (666666).

It can be divided in two parts, 5406 and 21, that multiplied together give a triangular number (113526 = T₄₇₆).

The spelling of 540621 in words is "five hundred forty thousand, six hundred twenty-one".