78631579 has 8 divisors (see below), whose sum is σ = 89661600. Its totient is φ = 68313216.

The previous prime is 78631573. The next prime is 78631583. The reversal of 78631579 is 97513687.

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 78631579 - 2¹⁷ = 78500507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78631573) 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, 177679 + ... + 178120.

It is an arithmetic number, because the mean of its divisors is an integer number (11207700).

Almost surely, 2^78631579 is an apocalyptic number.

78631579 is a deficient number, since it is larger than the sum of its proper divisors (11030021).

78631579 is a wasteful number, since it uses less digits than its factorization.

78631579 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355829.

The product of its digits is 317520, while the sum is 46.

The square root of 78631579 is about 8867.4448969249. Note that the first 3 decimals coincide. The cubic root of 78631579 is about 428.4159838221.

The spelling of 78631579 in words is "seventy-eight million, six hundred thirty-one thousand, five hundred seventy-nine".