20078257 has 2 divisors, whose sum is σ = 20078258. Its totient is φ = 20078256.

The previous prime is 20078249. The next prime is 20078273. The reversal of 20078257 is 75287002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20034576 + 43681 = 4476^2 + 209^2 .

It is a cyclic number.

It is not a de Polignac number, because 20078257 - 2³ = 20078249 is a prime.

It is equal to p_1275295 and since 20078257 and 1275295 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20078957) 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, 10039128 + 10039129.

It is an arithmetic number, because the mean of its divisors is an integer number (10039129).

Almost surely, 2^20078257 is an apocalyptic number.

It is an amenable number.

20078257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20078257 is an equidigital number, since it uses as much as digits as its factorization.

20078257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7840, while the sum is 31.

The square root of 20078257 is about 4480.8768115180. The cubic root of 20078257 is about 271.7953378619.

The spelling of 20078257 in words is "twenty million, seventy-eight thousand, two hundred fifty-seven".