20430953 has 4 divisors (see below), whose sum is σ = 21090048. Its totient is φ = 19771860.

The previous prime is 20430941. The next prime is 20430973. The reversal of 20430953 is 35903402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 35903402 = 2 ⋅17951701.

It is a cyclic number.

It is not a de Polignac number, because 20430953 - 2⁴ = 20430937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20430973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 329501 + ... + 329562.

It is an arithmetic number, because the mean of its divisors is an integer number (5272512).

Almost surely, 2^20430953 is an apocalyptic number.

It is an amenable number.

20430953 is a deficient number, since it is larger than the sum of its proper divisors (659095).

20430953 is an equidigital number, since it uses as much as digits as its factorization.

20430953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659094.

The product of its (nonzero) digits is 3240, while the sum is 26.

The square root of 20430953 is about 4520.0611721524. The cubic root of 20430953 is about 273.3775675321.

The spelling of 20430953 in words is "twenty million, four hundred thirty thousand, nine hundred fifty-three".