78880421 has 2 divisors, whose sum is σ = 78880422. Its totient is φ = 78880420.

The previous prime is 78880397. The next prime is 78880453. The reversal of 78880421 is 12408887.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 56460196 + 22420225 = 7514^2 + 4735^2 .

It is a cyclic number.

It is not a de Polignac number, because 78880421 - 2¹⁸ = 78618277 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78880481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39440210 + 39440211.

It is an arithmetic number, because the mean of its divisors is an integer number (39440211).

Almost surely, 2^78880421 is an apocalyptic number.

It is an amenable number.

78880421 is a deficient number, since it is larger than the sum of its proper divisors (1).

78880421 is an equidigital number, since it uses as much as digits as its factorization.

78880421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28672, while the sum is 38.

The square root of 78880421 is about 8881.4650255462. The cubic root of 78880421 is about 428.8674378467.

The spelling of 78880421 in words is "seventy-eight million, eight hundred eighty thousand, four hundred twenty-one".