78721801 has 8 divisors (see below), whose sum is σ = 83695680. Its totient is φ = 73877232.

The previous prime is 78721793. The next prime is 78721837. The reversal of 78721801 is 10812787.

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 78721801 - 2³ = 78721793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78721891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31071 + ... + 33508.

It is an arithmetic number, because the mean of its divisors is an integer number (10461960).

Almost surely, 2^78721801 is an apocalyptic number.

It is an amenable number.

78721801 is a deficient number, since it is larger than the sum of its proper divisors (4973879).

78721801 is a wasteful number, since it uses less digits than its factorization.

78721801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64655.

The product of its (nonzero) digits is 6272, while the sum is 34.

The square root of 78721801 is about 8872.5306987353. The cubic root of 78721801 is about 428.5797762554.

The spelling of 78721801 in words is "seventy-eight million, seven hundred twenty-one thousand, eight hundred one".