538251561 has 24 divisors (see below), whose sum is σ = 810561024. Its totient is φ = 356924880.

The previous prime is 538251547. The next prime is 538251563. The reversal of 538251561 is 165152835.

It is a happy number.

538251561 is a `hidden beast` number, since 5 + 3 + 82 + 515 + 61 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-538251561 is a prime.

It is not an unprimeable number, because it can be changed into a prime (538251563) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40615 + ... + 52211.

It is an arithmetic number, because the mean of its divisors is an integer number (33773376).

Almost surely, 2^538251561 is an apocalyptic number.

It is an amenable number.

538251561 is a deficient number, since it is larger than the sum of its proper divisors (272309463).

538251561 is a wasteful number, since it uses less digits than its factorization.

538251561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11803 (or 11791 counting only the distinct ones).

The product of its digits is 36000, while the sum is 36.

The square root of 538251561 is about 23200.2491581448. The cubic root of 538251561 is about 813.4454469916.

The spelling of 538251561 in words is "five hundred thirty-eight million, two hundred fifty-one thousand, five hundred sixty-one".