77391309 has 16 divisors (see below), whose sum is σ = 106235840. Its totient is φ = 50077440.

The previous prime is 77391277. The next prime is 77391311. The reversal of 77391309 is 90319377.

It is not a de Polignac number, because 77391309 - 2⁵ = 77391277 is a prime.

It is a super-3 number, since 3×77391309³ (a number of 25 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77391319) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76197 + ... + 77205.

It is an arithmetic number, because the mean of its divisors is an integer number (6639740).

Almost surely, 2^77391309 is an apocalyptic number.

It is an amenable number.

77391309 is a deficient number, since it is larger than the sum of its proper divisors (28844531).

77391309 is a wasteful number, since it uses less digits than its factorization.

77391309 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1740.

The product of its (nonzero) digits is 35721, while the sum is 39.

The square root of 77391309 is about 8797.2330309024. The cubic root of 77391309 is about 426.1515418886.

The spelling of 77391309 in words is "seventy-seven million, three hundred ninety-one thousand, three hundred nine".