78462221 has 2 divisors, whose sum is σ = 78462222. Its totient is φ = 78462220.

The previous prime is 78462217. The next prime is 78462239. The reversal of 78462221 is 12226487.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 49420900 + 29041321 = 7030^2 + 5389^2 .

It is a cyclic number.

It is not a de Polignac number, because 78462221 - 2² = 78462217 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78462211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39231110 + 39231111.

It is an arithmetic number, because the mean of its divisors is an integer number (39231111).

Almost surely, 2^78462221 is an apocalyptic number.

It is an amenable number.

78462221 is a deficient number, since it is larger than the sum of its proper divisors (1).

78462221 is an equidigital number, since it uses as much as digits as its factorization.

78462221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10752, while the sum is 32.

The square root of 78462221 is about 8857.8903244509. The cubic root of 78462221 is about 428.1081862507.

The spelling of 78462221 in words is "seventy-eight million, four hundred sixty-two thousand, two hundred twenty-one".