39951887389 has 2 divisors, whose sum is σ = 39951887390. Its totient is φ = 39951887388.

The previous prime is 39951887383. The next prime is 39951887411. The reversal of 39951887389 is 98378815993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34920396900 + 5031490489 = 186870^2 + 70933^2 .

It is an emirp because it is prime and its reverse (98378815993) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39951887389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39951887383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19975943694 + 19975943695.

It is an arithmetic number, because the mean of its divisors is an integer number (19975943695).

Almost surely, 2^39951887389 is an apocalyptic number.

It is an amenable number.

39951887389 is a deficient number, since it is larger than the sum of its proper divisors (1).

39951887389 is an equidigital number, since it uses as much as digits as its factorization.

39951887389 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 117573120, while the sum is 70.

The spelling of 39951887389 in words is "thirty-nine billion, nine hundred fifty-one million, eight hundred eighty-seven thousand, three hundred eighty-nine".