20880257 has 2 divisors, whose sum is σ = 20880258. Its totient is φ = 20880256.

The previous prime is 20880191. The next prime is 20880269. The reversal of 20880257 is 75208802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19722481 + 1157776 = 4441^2 + 1076^2 .

It is a cyclic number.

It is not a de Polignac number, because 20880257 - 2⁸ = 20880001 is a prime.

It is equal to p_1322879 and since 20880257 and 1322879 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 (20883257) 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, 10440128 + 10440129.

It is an arithmetic number, because the mean of its divisors is an integer number (10440129).

Almost surely, 2^20880257 is an apocalyptic number.

It is an amenable number.

20880257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20880257 is an equidigital number, since it uses as much as digits as its factorization.

20880257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8960, while the sum is 32.

The square root of 20880257 is about 4569.4919848929. The cubic root of 20880257 is about 275.3670338804.

The spelling of 20880257 in words is "twenty million, eight hundred eighty thousand, two hundred fifty-seven".