77947049 has 4 divisors (see below), whose sum is σ = 80053764. Its totient is φ = 75840336.

The previous prime is 77947031. The next prime is 77947073. The reversal of 77947049 is 94074977.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 32855824 + 45091225 = 5732^2 + 6715^2 .

It is a cyclic number.

It is not a de Polignac number, because 77947049 - 2²⁰ = 76898473 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77946994 and 77947012.

It is not an unprimeable number, because it can be changed into a prime (77947019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1053302 + ... + 1053375.

It is an arithmetic number, because the mean of its divisors is an integer number (20013441).

Almost surely, 2^77947049 is an apocalyptic number.

It is an amenable number.

77947049 is a deficient number, since it is larger than the sum of its proper divisors (2106715).

77947049 is a wasteful number, since it uses less digits than its factorization.

77947049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2106714.

The product of its (nonzero) digits is 444528, while the sum is 47.

The square root of 77947049 is about 8828.7625973293. The cubic root of 77947049 is about 427.1691618602.

The spelling of 77947049 in words is "seventy-seven million, nine hundred forty-seven thousand, forty-nine".