20259649 has 2 divisors, whose sum is σ = 20259650. Its totient is φ = 20259648.

The previous prime is 20259641. The next prime is 20259653. The reversal of 20259649 is 94695202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17073424 + 3186225 = 4132^2 + 1785^2 .

It is a cyclic number.

It is not a de Polignac number, because 20259649 - 2³ = 20259641 is a prime.

It is not a weakly prime, because it can be changed into another prime (20259641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10129824 + 10129825.

It is an arithmetic number, because the mean of its divisors is an integer number (10129825).

Almost surely, 2^20259649 is an apocalyptic number.

It is an amenable number.

20259649 is a deficient number, since it is larger than the sum of its proper divisors (1).

20259649 is an equidigital number, since it uses as much as digits as its factorization.

20259649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 20259649 is about 4501.0719834279. The cubic root of 20259649 is about 272.6113743877.

The spelling of 20259649 in words is "twenty million, two hundred fifty-nine thousand, six hundred forty-nine".