78327509 has 16 divisors (see below), whose sum is σ = 85895040. Its totient is φ = 70994880.

The previous prime is 78327503. The next prime is 78327541. The reversal of 78327509 is 90572387.

It is a cyclic number.

It is not a de Polignac number, because 78327509 - 2²⁰ = 77278933 is a prime.

It is a super-2 number, since 2×78327509² = 12270397332290162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78327503) 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, 236474 + ... + 236804.

It is an arithmetic number, because the mean of its divisors is an integer number (5368440).

Almost surely, 2^78327509 is an apocalyptic number.

It is an amenable number.

78327509 is a deficient number, since it is larger than the sum of its proper divisors (7567531).

78327509 is a wasteful number, since it uses less digits than its factorization.

78327509 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 620.

The product of its (nonzero) digits is 105840, while the sum is 41.

The square root of 78327509 is about 8850.2829898258. The cubic root of 78327509 is about 427.8630391973.

The spelling of 78327509 in words is "seventy-eight million, three hundred twenty-seven thousand, five hundred nine".