78402229 has 2 divisors, whose sum is σ = 78402230. Its totient is φ = 78402228.

The previous prime is 78402199. The next prime is 78402271. The reversal of 78402229 is 92220487.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51122500 + 27279729 = 7150^2 + 5223^2 .

It is a cyclic number.

It is not a de Polignac number, because 78402229 - 2¹³ = 78394037 is a prime.

It is a super-2 number, since 2×78402229² = 12293819024336882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78402194 and 78402203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78408229) 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 as a sum of consecutive naturals, namely, 39201114 + 39201115.

It is an arithmetic number, because the mean of its divisors is an integer number (39201115).

Almost surely, 2^78402229 is an apocalyptic number.

It is an amenable number.

78402229 is a deficient number, since it is larger than the sum of its proper divisors (1).

78402229 is an equidigital number, since it uses as much as digits as its factorization.

78402229 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 78402229 is about 8854.5033175215. The cubic root of 78402229 is about 427.9990483136. Note that the first 3 decimals are identical.

The spelling of 78402229 in words is "seventy-eight million, four hundred two thousand, two hundred twenty-nine".