76663221 has 4 divisors (see below), whose sum is σ = 102217632. Its totient is φ = 51108812.

The previous prime is 76663219. The next prime is 76663231. The reversal of 76663221 is 12236667.

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 76663221 - 2¹ = 76663219 is a prime.

It is a Curzon number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (76663201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12777201 + ... + 12777206.

It is an arithmetic number, because the mean of its divisors is an integer number (25554408).

Almost surely, 2^76663221 is an apocalyptic number.

It is an amenable number.

76663221 is a deficient number, since it is larger than the sum of its proper divisors (25554411).

76663221 is a wasteful number, since it uses less digits than its factorization.

76663221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25554410.

The product of its digits is 18144, while the sum is 33.

The square root of 76663221 is about 8755.7535940660. The cubic root of 76663221 is about 424.8109350518.

Adding to 76663221 its reverse (12236667), we get a palindrome (88899888).

The spelling of 76663221 in words is "seventy-six million, six hundred sixty-three thousand, two hundred twenty-one".