78155077787 has 2 divisors, whose sum is σ = 78155077788. Its totient is φ = 78155077786.

The previous prime is 78155077739. The next prime is 78155077919. The reversal of 78155077787 is 78777055187.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78155077787 - 2¹² = 78155073691 is a prime.

It is a super-2 number, since 2×78155077787² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78155077387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39077538893 + 39077538894.

It is an arithmetic number, because the mean of its divisors is an integer number (39077538894).

Almost surely, 2^78155077787 is an apocalyptic number.

78155077787 is a deficient number, since it is larger than the sum of its proper divisors (1).

78155077787 is an equidigital number, since it uses as much as digits as its factorization.

78155077787 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26891200, while the sum is 62.

The spelling of 78155077787 in words is "seventy-eight billion, one hundred fifty-five million, seventy-seven thousand, seven hundred eighty-seven".