20351243 has 16 divisors (see below), whose sum is σ = 23189760. Its totient is φ = 17690400.

The previous prime is 20351239. The next prime is 20351257. The reversal of 20351243 is 34215302.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20351243 - 2² = 20351239 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20351263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41546 + ... + 42032.

It is an arithmetic number, because the mean of its divisors is an integer number (1449360).

Almost surely, 2^20351243 is an apocalyptic number.

20351243 is a deficient number, since it is larger than the sum of its proper divisors (2838517).

20351243 is a wasteful number, since it uses less digits than its factorization.

20351243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 658.

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 20351243 is about 4511.2351967061. The cubic root of 20351243 is about 273.0215827328.

Adding to 20351243 its reverse (34215302), we get a palindrome (54566545).

The spelling of 20351243 in words is "twenty million, three hundred fifty-one thousand, two hundred forty-three".