38721618246557 has 2 divisors, whose sum is σ = 38721618246558. Its totient is φ = 38721618246556.

The previous prime is 38721618246527. The next prime is 38721618246559. The reversal of 38721618246557 is 75564281612783.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29998963991161 + 8722654255396 = 5477131^2 + 2953414^2 .

It is a cyclic number.

It is not a de Polignac number, because 38721618246557 - 2²⁶ = 38721551137693 is a prime.

Together with 38721618246559, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 38721618246493 and 38721618246502.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38721618246559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19360809123278 + 19360809123279.

It is an arithmetic number, because the mean of its divisors is an integer number (19360809123279).

Almost surely, 2^{38721618246557} is an apocalyptic number.

It is an amenable number.

38721618246557 is a deficient number, since it is larger than the sum of its proper divisors (1).

38721618246557 is an equidigital number, since it uses as much as digits as its factorization.

38721618246557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 135475200, while the sum is 65.

The spelling of 38721618246557 in words is "thirty-eight trillion, seven hundred twenty-one billion, six hundred eighteen million, two hundred forty-six thousand, five hundred fifty-seven".