71678433649 has 4 divisors (see below), whose sum is σ = 72042283764. Its totient is φ = 71314583536.

The previous prime is 71678433643. The next prime is 71678433653. The reversal of 71678433649 is 94633487617.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94633487617 = 82237 ⋅1150741.

It can be written as a sum of positive squares in 2 ways, for example, as 70938593649 + 739840000 = 266343^2 + 27200^2 .

It is a cyclic number.

It is not a de Polignac number, because 71678433649 - 2⁹ = 71678433137 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71678433593 and 71678433602.

It is not an unprimeable number, because it can be changed into a prime (71678433643) 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, 181924762 + ... + 181925155.

It is an arithmetic number, because the mean of its divisors is an integer number (18010570941).

Almost surely, 2^71678433649 is an apocalyptic number.

It is an amenable number.

71678433649 is a deficient number, since it is larger than the sum of its proper divisors (363850115).

71678433649 is a wasteful number, since it uses less digits than its factorization.

71678433649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363850114.

The product of its digits is 18289152, while the sum is 58.

The spelling of 71678433649 in words is "seventy-one billion, six hundred seventy-eight million, four hundred thirty-three thousand, six hundred forty-nine".