38403440639 has 2 divisors, whose sum is σ = 38403440640. Its totient is φ = 38403440638.

The previous prime is 38403440611. The next prime is 38403440651. The reversal of 38403440639 is 93604430483.

It is a strong prime.

It is an emirp because it is prime and its reverse (93604430483) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-38403440639 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 38403440639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38403440939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19201720319 + 19201720320.

It is an arithmetic number, because the mean of its divisors is an integer number (19201720320).

Almost surely, 2^38403440639 is an apocalyptic number.

38403440639 is a deficient number, since it is larger than the sum of its proper divisors (1).

38403440639 is an equidigital number, since it uses as much as digits as its factorization.

38403440639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 746496, while the sum is 44.

The spelling of 38403440639 in words is "thirty-eight billion, four hundred three million, four hundred forty thousand, six hundred thirty-nine".