538642261 has 8 divisors (see below), whose sum is σ = 553122584. Its totient is φ = 524344320.

The previous prime is 538642249. The next prime is 538642283. The reversal of 538642261 is 162246835.

It can be written as a sum of positive squares in 4 ways, for example, as 24940036 + 513702225 = 4994^2 + 22665^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 538642261 - 2¹¹ = 538640213 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 538642261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (538642061) 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, 39600 + ... + 51433.

It is an arithmetic number, because the mean of its divisors is an integer number (69140323).

Almost surely, 2^538642261 is an apocalyptic number.

It is an amenable number.

538642261 is a deficient number, since it is larger than the sum of its proper divisors (14480323).

538642261 is an equidigital number, since it uses as much as digits as its factorization.

538642261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91191.

The product of its digits is 69120, while the sum is 37.

The square root of 538642261 is about 23208.6677989065. The cubic root of 538642261 is about 813.6422176055.

The spelling of 538642261 in words is "five hundred thirty-eight million, six hundred forty-two thousand, two hundred sixty-one".