78526391 has 8 divisors (see below), whose sum is σ = 79910640. Its totient is φ = 77153472.

The previous prime is 78526387. The next prime is 78526397. The reversal of 78526391 is 19362587.

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 78526391 - 2² = 78526387 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 (78526397) 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, 11801 + ... + 17213.

It is an arithmetic number, because the mean of its divisors is an integer number (9988830).

Almost surely, 2^78526391 is an apocalyptic number.

78526391 is a deficient number, since it is larger than the sum of its proper divisors (1384249).

78526391 is a wasteful number, since it uses less digits than its factorization.

78526391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5665.

The product of its digits is 90720, while the sum is 41.

The square root of 78526391 is about 8861.5117784721. The cubic root of 78526391 is about 428.2248632797.

The spelling of 78526391 in words is "seventy-eight million, five hundred twenty-six thousand, three hundred ninety-one".