78575221 has 4 divisors (see below), whose sum is σ = 78735744. Its totient is φ = 78414700.

The previous prime is 78575219. The next prime is 78575227. The reversal of 78575221 is 12257587.

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 78575221 - 2¹ = 78575219 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 (78575227) 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 3 ways as a sum of consecutive naturals, for example, 79525 + ... + 80506.

It is an arithmetic number, because the mean of its divisors is an integer number (19683936).

Almost surely, 2^78575221 is an apocalyptic number.

It is an amenable number.

78575221 is a deficient number, since it is larger than the sum of its proper divisors (160523).

78575221 is a wasteful number, since it uses less digits than its factorization.

78575221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160522.

The product of its digits is 39200, while the sum is 37.

The square root of 78575221 is about 8864.2665235201. The cubic root of 78575221 is about 428.3136057908.

The spelling of 78575221 in words is "seventy-eight million, five hundred seventy-five thousand, two hundred twenty-one".