39978629 has 2 divisors, whose sum is σ = 39978630. Its totient is φ = 39978628.

The previous prime is 39978593. The next prime is 39978667. The reversal of 39978629 is 92687993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33373729 + 6604900 = 5777^2 + 2570^2 .

It is an emirp because it is prime and its reverse (92687993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 39978629 - 2¹² = 39974533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39978229) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19989314 + 19989315.

It is an arithmetic number, because the mean of its divisors is an integer number (19989315).

Almost surely, 2^39978629 is an apocalyptic number.

It is an amenable number.

39978629 is a deficient number, since it is larger than the sum of its proper divisors (1).

39978629 is an equidigital number, since it uses as much as digits as its factorization.

39978629 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1469664, while the sum is 53.

The square root of 39978629 is about 6322.8655687117. The cubic root of 39978629 is about 341.9342719919.

The spelling of 39978629 in words is "thirty-nine million, nine hundred seventy-eight thousand, six hundred twenty-nine".