538206118551661 has 12 divisors (see below), whose sum is σ = 628403927221980. Its totient is φ = 459604587684480.

The previous prime is 538206118551649. The next prime is 538206118551667. The reversal of 538206118551661 is 166155811602835.

It can be written as a sum of positive squares in 2 ways, for example, as 45512361301225 + 492693757250436 = 6746285^2 + 22196706^2 .

It is not a de Polignac number, because 538206118551661 - 2¹¹ = 538206118549613 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 538206118551596 and 538206118551605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (538206118551667) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20415968860 + ... + 20415995221.

It is an arithmetic number, because the mean of its divisors is an integer number (52366993935165).

Almost surely, 2^{538206118551661} is an apocalyptic number.

It is an amenable number.

538206118551661 is a deficient number, since it is larger than the sum of its proper divisors (90197808670319).

538206118551661 is a wasteful number, since it uses less digits than its factorization.

538206118551661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40831964364 (or 40831964357 counting only the distinct ones).

The product of its (nonzero) digits is 10368000, while the sum is 58.

The spelling of 538206118551661 in words is "five hundred thirty-eight trillion, two hundred six billion, one hundred eighteen million, five hundred fifty-one thousand, six hundred sixty-one".