77864816149 has 4 divisors (see below), whose sum is σ = 77882667136. Its totient is φ = 77846965164.

The previous prime is 77864816143. The next prime is 77864816189. The reversal of 77864816149 is 94161846877.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 94161846877 = 7 ⋅13451692411.

It is a cyclic number.

It is not a de Polignac number, because 77864816149 - 2³¹ = 75717332501 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77864816143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8918949 + ... + 8927674.

It is an arithmetic number, because the mean of its divisors is an integer number (19470666784).

Almost surely, 2^77864816149 is an apocalyptic number.

It is an amenable number.

77864816149 is a deficient number, since it is larger than the sum of its proper divisors (17850987).

77864816149 is a wasteful number, since it uses less digits than its factorization.

77864816149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17850986.

The product of its digits is 16257024, while the sum is 61.

The spelling of 77864816149 in words is "seventy-seven billion, eight hundred sixty-four million, eight hundred sixteen thousand, one hundred forty-nine".