39978229 has 2 divisors, whose sum is σ = 39978230. Its totient is φ = 39978228.

The previous prime is 39978227. The next prime is 39978233. The reversal of 39978229 is 92287993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26801329 + 13176900 = 5177^2 + 3630^2 .

It is a cyclic number.

It is not a de Polignac number, because 39978229 - 2¹ = 39978227 is a prime.

Together with 39978227, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39978221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19989114 + 19989115.

It is an arithmetic number, because the mean of its divisors is an integer number (19989115).

Almost surely, 2^39978229 is an apocalyptic number.

It is an amenable number.

39978229 is a deficient number, since it is larger than the sum of its proper divisors (1).

39978229 is an equidigital number, since it uses as much as digits as its factorization.

39978229 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 489888, while the sum is 49.

The square root of 39978229 is about 6322.8339374050. The cubic root of 39978229 is about 341.9331315979.

The spelling of 39978229 in words is "thirty-nine million, nine hundred seventy-eight thousand, two hundred twenty-nine".