38616821 has 2 divisors, whose sum is σ = 38616822. Its totient is φ = 38616820.

The previous prime is 38616817. The next prime is 38616869. The reversal of 38616821 is 12861683.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38613796 + 3025 = 6214^2 + 55^2 .

It is a cyclic number.

It is not a de Polignac number, because 38616821 - 2² = 38616817 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38616811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19308410 + 19308411.

It is an arithmetic number, because the mean of its divisors is an integer number (19308411).

Almost surely, 2^38616821 is an apocalyptic number.

It is an amenable number.

38616821 is a deficient number, since it is larger than the sum of its proper divisors (1).

38616821 is an equidigital number, since it uses as much as digits as its factorization.

38616821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 35.

The square root of 38616821 is about 6214.2433972287. The cubic root of 38616821 is about 338.0068536126.

It can be divided in two parts, 3861682 and 1, that added together give a palindrome (3861683).

The spelling of 38616821 in words is "thirty-eight million, six hundred sixteen thousand, eight hundred twenty-one".