38644381 has 2 divisors, whose sum is σ = 38644382. Its totient is φ = 38644380.

The previous prime is 38644379. The next prime is 38644399. The reversal of 38644381 is 18344683.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35295481 + 3348900 = 5941^2 + 1830^2 .

It is a cyclic number.

It is not a de Polignac number, because 38644381 - 2¹ = 38644379 is a prime.

It is a super-2 number, since 2×38644381² = 2986776365746322, which contains 22 as substring.

Together with 38644379, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 38644381.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38641381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19322190 + 19322191.

It is an arithmetic number, because the mean of its divisors is an integer number (19322191).

Almost surely, 2^38644381 is an apocalyptic number.

It is an amenable number.

38644381 is a deficient number, since it is larger than the sum of its proper divisors (1).

38644381 is an equidigital number, since it uses as much as digits as its factorization.

38644381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 55296, while the sum is 37.

The square root of 38644381 is about 6216.4604880913. The cubic root of 38644381 is about 338.0872439144.

The spelling of 38644381 in words is "thirty-eight million, six hundred forty-four thousand, three hundred eighty-one".