78078401 has 2 divisors, whose sum is σ = 78078402. Its totient is φ = 78078400.

The previous prime is 78078397. The next prime is 78078409. The reversal of 78078401 is 10487087.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77440000 + 638401 = 8800^2 + 799^2 .

It is a cyclic number.

It is not a de Polignac number, because 78078401 - 2² = 78078397 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78078409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39039200 + 39039201.

It is an arithmetic number, because the mean of its divisors is an integer number (39039201).

Almost surely, 2^78078401 is an apocalyptic number.

It is an amenable number.

78078401 is a deficient number, since it is larger than the sum of its proper divisors (1).

78078401 is an equidigital number, since it uses as much as digits as its factorization.

78078401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12544, while the sum is 35.

The square root of 78078401 is about 8836.1983341254. The cubic root of 78078401 is about 427.4089743842.

The spelling of 78078401 in words is "seventy-eight million, seventy-eight thousand, four hundred one".