78901139 has 2 divisors, whose sum is σ = 78901140. Its totient is φ = 78901138.

The previous prime is 78901133. The next prime is 78901157. The reversal of 78901139 is 93110987.

It is a weak prime.

It is an emirp because it is prime and its reverse (93110987) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78901139 is a prime.

It is not a weakly prime, because it can be changed into another prime (78901133) 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, 39450569 + 39450570.

It is an arithmetic number, because the mean of its divisors is an integer number (39450570).

Almost surely, 2^78901139 is an apocalyptic number.

78901139 is a deficient number, since it is larger than the sum of its proper divisors (1).

78901139 is an equidigital number, since it uses as much as digits as its factorization.

78901139 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 38.

The square root of 78901139 is about 8882.6313105971. The cubic root of 78901139 is about 428.9049820081.

It can be divided in two parts, 7890113 and 9, that multiplied together give a palindrome (71011017).

The spelling of 78901139 in words is "seventy-eight million, nine hundred one thousand, one hundred thirty-nine".