39997387 has 2 divisors, whose sum is σ = 39997388. Its totient is φ = 39997386.

The previous prime is 39997381. The next prime is 39997469. The reversal of 39997387 is 78379993.

It is a weak prime.

It is an emirp because it is prime and its reverse (78379993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 39997387 - 2²³ = 31608779 is a prime.

It is not a weakly prime, because it can be changed into another prime (39997381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19998693 + 19998694.

It is an arithmetic number, because the mean of its divisors is an integer number (19998694).

Almost surely, 2^39997387 is an apocalyptic number.

39997387 is a deficient number, since it is larger than the sum of its proper divisors (1).

39997387 is an equidigital number, since it uses as much as digits as its factorization.

39997387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2571912, while the sum is 55.

The square root of 39997387 is about 6324.3487411749. The cubic root of 39997387 is about 341.9877422279.

The spelling of 39997387 in words is "thirty-nine million, nine hundred ninety-seven thousand, three hundred eighty-seven".