77891886019 has 2 divisors, whose sum is σ = 77891886020. Its totient is φ = 77891886018.

The previous prime is 77891886013. The next prime is 77891886077. The reversal of 77891886019 is 91068819877.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 77891886019 - 2¹³ = 77891877827 is a prime.

It is a super-2 number, since 2×77891886019² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (77891886013) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38945943009 + 38945943010.

It is an arithmetic number, because the mean of its divisors is an integer number (38945943010).

Almost surely, 2^77891886019 is an apocalyptic number.

77891886019 is a deficient number, since it is larger than the sum of its proper divisors (1).

77891886019 is an equidigital number, since it uses as much as digits as its factorization.

77891886019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12192768, while the sum is 64.

The spelling of 77891886019 in words is "seventy-seven billion, eight hundred ninety-one million, eight hundred eighty-six thousand, nineteen".