77971309 has 8 divisors (see below), whose sum is σ = 84785792. Its totient is φ = 71273520.

The previous prime is 77971303. The next prime is 77971319. The reversal of 77971309 is 90317977.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77971309 - 2³ = 77971301 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77971301) 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, 27777 + ... + 30454.

It is an arithmetic number, because the mean of its divisors is an integer number (10598224).

Almost surely, 2^77971309 is an apocalyptic number.

It is an amenable number.

77971309 is a deficient number, since it is larger than the sum of its proper divisors (6814483).

77971309 is a wasteful number, since it uses less digits than its factorization.

77971309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58347.

The product of its (nonzero) digits is 83349, while the sum is 43.

The square root of 77971309 is about 8830.1364089124. The cubic root of 77971309 is about 427.2134742023.

The spelling of 77971309 in words is "seventy-seven million, nine hundred seventy-one thousand, three hundred nine".