506981 has 4 divisors (see below), whose sum is σ = 509964. Its totient is φ = 504000.

The previous prime is 506963. The next prime is 506983. The reversal of 506981 is 189605.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 96100 + 410881 = 310^2 + 641^2 .

It is a cyclic number.

It is not a de Polignac number, because 506981 - 2¹⁸ = 244837 is a prime.

It is a super-2 number, since 2×506981² = 514059468722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 506981.

It is not an unprimeable number, because it can be changed into a prime (506983) 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, 1220 + ... + 1581.

It is an arithmetic number, because the mean of its divisors is an integer number (127491).

2⁵⁰⁶⁹⁸¹ is an apocalyptic number.

It is an amenable number.

506981 is a deficient number, since it is larger than the sum of its proper divisors (2983).

506981 is a wasteful number, since it uses less digits than its factorization.

506981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2982.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 506981 is about 712.0259826720. The cubic root of 506981 is about 79.7377349023.

The spelling of 506981 in words is "five hundred six thousand, nine hundred eighty-one".