78497309 has 8 divisors (see below), whose sum is σ = 85969728. Its totient is φ = 71080960.

The previous prime is 78497297. The next prime is 78497311. The reversal of 78497309 is 90379487.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78497309 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78497359) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11057 + ... + 16710.

It is an arithmetic number, because the mean of its divisors is an integer number (10746216).

Almost surely, 2^78497309 is an apocalyptic number.

It is an amenable number.

78497309 is a deficient number, since it is larger than the sum of its proper divisors (7472419).

78497309 is a wasteful number, since it uses less digits than its factorization.

78497309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28035.

The product of its (nonzero) digits is 381024, while the sum is 47.

The square root of 78497309 is about 8859.8707101176. The cubic root of 78497309 is about 428.1719928455.

The spelling of 78497309 in words is "seventy-eight million, four hundred ninety-seven thousand, three hundred nine".