77211017644 has 24 divisors (see below), whose sum is σ = 137817323280. Its totient is φ = 37838524416.

The previous prime is 77211017627. The next prime is 77211017647. The reversal of 77211017644 is 44671011277.

It is a junction number, because it is equal to n+sod(n) for n = 77211017597 and 77211017606.

It is not an unprimeable number, because it can be changed into a prime (77211017647) 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 in 7 ways as a sum of consecutive naturals, for example, 405877 + ... + 564940.

It is an arithmetic number, because the mean of its divisors is an integer number (5742388470).

Almost surely, 2^77211017644 is an apocalyptic number.

It is an amenable number.

77211017644 is a deficient number, since it is larger than the sum of its proper divisors (60606305636).

77211017644 is a wasteful number, since it uses less digits than its factorization.

77211017644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971217 (or 971215 counting only the distinct ones).

The product of its (nonzero) digits is 65856, while the sum is 40.

The spelling of 77211017644 in words is "seventy-seven billion, two hundred eleven million, seventeen thousand, six hundred forty-four".