78042529 has 8 divisors (see below), whose sum is σ = 82767528. Its totient is φ = 73332480.

The previous prime is 78042527. The next prime is 78042539. The reversal of 78042529 is 92524087.

It can be written as a sum of positive squares in 4 ways, for example, as 44957025 + 33085504 = 6705^2 + 5752^2 .

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 78042529 - 2¹ = 78042527 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78042527) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8119 + ... + 14899.

It is an arithmetic number, because the mean of its divisors is an integer number (10345941).

Almost surely, 2^78042529 is an apocalyptic number.

It is an amenable number.

78042529 is a deficient number, since it is larger than the sum of its proper divisors (4724999).

78042529 is a wasteful number, since it uses less digits than its factorization.

78042529 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7475.

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 78042529 is about 8834.1682687166. The cubic root of 78042529 is about 427.3435087191.

The spelling of 78042529 in words is "seventy-eight million, forty-two thousand, five hundred twenty-nine".