20343649 has 2 divisors, whose sum is σ = 20343650. Its totient is φ = 20343648.

The previous prime is 20343643. The next prime is 20343677. The reversal of 20343649 is 94634302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17305600 + 3038049 = 4160^2 + 1743^2 .

It is a cyclic number.

It is not a de Polignac number, because 20343649 - 2⁹ = 20343137 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20343649.

It is not a weakly prime, because it can be changed into another prime (20343643) 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, 10171824 + 10171825.

It is an arithmetic number, because the mean of its divisors is an integer number (10171825).

Almost surely, 2^20343649 is an apocalyptic number.

It is an amenable number.

20343649 is a deficient number, since it is larger than the sum of its proper divisors (1).

20343649 is an equidigital number, since it uses as much as digits as its factorization.

20343649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 31.

The square root of 20343649 is about 4510.3934418186. The cubic root of 20343649 is about 272.9876194701.

The spelling of 20343649 in words is "twenty million, three hundred forty-three thousand, six hundred forty-nine".