78668929 has 4 divisors (see below), whose sum is σ = 80342784. Its totient is φ = 76995076.

The previous prime is 78668881. The next prime is 78668981. The reversal of 78668929 is 92986687.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78668929 - 2¹³ = 78660737 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78668929.

It is not an unprimeable number, because it can be changed into a prime (78660929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 836857 + ... + 836950.

It is an arithmetic number, because the mean of its divisors is an integer number (20085696).

Almost surely, 2^78668929 is an apocalyptic number.

It is an amenable number.

78668929 is a deficient number, since it is larger than the sum of its proper divisors (1673855).

78668929 is a wasteful number, since it uses less digits than its factorization.

78668929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1673854.

The product of its digits is 2612736, while the sum is 55.

The square root of 78668929 is about 8869.5506650563. The cubic root of 78668929 is about 428.4838056155.

It can be divided in two parts, 78668 and 929, that added together give a palindrome (79597).

The spelling of 78668929 in words is "seventy-eight million, six hundred sixty-eight thousand, nine hundred twenty-nine".