20430945 has 12 divisors (see below), whose sum is σ = 35413716. Its totient is φ = 10896480.

The previous prime is 20430941. The next prime is 20430973. The reversal of 20430945 is 54903402.

It can be written as a sum of positive squares in 2 ways, for example, as 9381969 + 11048976 = 3063^2 + 3324^2 .

It is not a de Polignac number, because 20430945 - 2² = 20430941 is a prime.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (20430941) 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 11 ways as a sum of consecutive naturals, for example, 226966 + ... + 227055.

It is an arithmetic number, because the mean of its divisors is an integer number (2951143).

Almost surely, 2^20430945 is an apocalyptic number.

It is an amenable number.

20430945 is a deficient number, since it is larger than the sum of its proper divisors (14982771).

20430945 is a wasteful number, since it uses less digits than its factorization.

20430945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 454032 (or 454029 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 20430945 is about 4520.0602872086. The cubic root of 20430945 is about 273.3775318506.

The spelling of 20430945 in words is "twenty million, four hundred thirty thousand, nine hundred forty-five".