278478001 has 2 divisors, whose sum is σ = 278478002. Its totient is φ = 278478000.

The previous prime is 278477999. The next prime is 278478017. The reversal of 278478001 is 100874872.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 203205025 + 75272976 = 14255^2 + 8676^2 .

It is a cyclic number.

It is not a de Polignac number, because 278478001 - 2¹ = 278477999 is a prime.

Together with 278477999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (278478061) 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, 139239000 + 139239001.

It is an arithmetic number, because the mean of its divisors is an integer number (139239001).

Almost surely, 2^278478001 is an apocalyptic number.

It is an amenable number.

278478001 is a deficient number, since it is larger than the sum of its proper divisors (1).

278478001 is an equidigital number, since it uses as much as digits as its factorization.

278478001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25088, while the sum is 37.

The square root of 278478001 is about 16687.6601415537. The cubic root of 278478001 is about 653.0257364036.

The spelling of 278478001 in words is "two hundred seventy-eight million, four hundred seventy-eight thousand, one".