38972821 has 2 divisors, whose sum is σ = 38972822. Its totient is φ = 38972820.

The previous prime is 38972807. The next prime is 38972851. The reversal of 38972821 is 12827983.

38972821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36120100 + 2852721 = 6010^2 + 1689^2 .

It is a cyclic number.

It is not a de Polignac number, because 38972821 - 2⁷ = 38972693 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38972851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19486410 + 19486411.

It is an arithmetic number, because the mean of its divisors is an integer number (19486411).

Almost surely, 2^38972821 is an apocalyptic number.

It is an amenable number.

38972821 is a deficient number, since it is larger than the sum of its proper divisors (1).

38972821 is an equidigital number, since it uses as much as digits as its factorization.

38972821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 40.

The square root of 38972821 is about 6242.8215575972. The cubic root of 38972821 is about 339.0423484424.

It can be divided in two parts, 38972 and 821, that added together give a palindrome (39793).

The spelling of 38972821 in words is "thirty-eight million, nine hundred seventy-two thousand, eight hundred twenty-one".