20873257 has 2 divisors, whose sum is σ = 20873258. Its totient is φ = 20873256.

The previous prime is 20873249. The next prime is 20873269. The reversal of 20873257 is 75237802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17842176 + 3031081 = 4224^2 + 1741^2 .

It is a cyclic number.

It is not a de Polignac number, because 20873257 - 2³ = 20873249 is a prime.

It is not a weakly prime, because it can be changed into another prime (20873207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10436628 + 10436629.

It is an arithmetic number, because the mean of its divisors is an integer number (10436629).

Almost surely, 2^20873257 is an apocalyptic number.

It is an amenable number.

20873257 is a deficient number, since it is larger than the sum of its proper divisors (1).

20873257 is an equidigital number, since it uses as much as digits as its factorization.

20873257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23520, while the sum is 34.

The square root of 20873257 is about 4568.7259712090. The cubic root of 20873257 is about 275.3362586417.

The spelling of 20873257 in words is "twenty million, eight hundred seventy-three thousand, two hundred fifty-seven".