78552221 has 8 divisors (see below), whose sum is σ = 88009824. Its totient is φ = 69480720.

The previous prime is 78552217. The next prime is 78552239. The reversal of 78552221 is 12225587.

It is a happy number.

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 78552221 - 2² = 78552217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78552211) 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, 96095 + ... + 96908.

It is an arithmetic number, because the mean of its divisors is an integer number (11001228).

Almost surely, 2^78552221 is an apocalyptic number.

It is an amenable number.

78552221 is a deficient number, since it is larger than the sum of its proper divisors (9457603).

78552221 is a wasteful number, since it uses less digits than its factorization.

78552221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193051.

The product of its digits is 11200, while the sum is 32.

The square root of 78552221 is about 8862.9690849060. The cubic root of 78552221 is about 428.2718107052.

The spelling of 78552221 in words is "seventy-eight million, five hundred fifty-two thousand, two hundred twenty-one".