538690561 has 4 divisors (see below), whose sum is σ = 546277824. Its totient is φ = 531103300.

The previous prime is 538690553. The next prime is 538690583. The reversal of 538690561 is 165096835.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 538690561 - 2³ = 538690553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (538690961) 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, 3793525 + ... + 3793666.

It is an arithmetic number, because the mean of its divisors is an integer number (136569456).

Almost surely, 2^538690561 is an apocalyptic number.

It is an amenable number.

538690561 is a deficient number, since it is larger than the sum of its proper divisors (7587263).

538690561 is an equidigital number, since it uses as much as digits as its factorization.

538690561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7587262.

The product of its (nonzero) digits is 194400, while the sum is 43.

The square root of 538690561 is about 23209.7083350912. The cubic root of 538690561 is about 813.6665366186. Note that the first 3 decimals are identical.

The spelling of 538690561 in words is "five hundred thirty-eight million, six hundred ninety thousand, five hundred sixty-one".