20430057 has 4 divisors (see below), whose sum is σ = 27240080. Its totient is φ = 13620036.

The previous prime is 20430041. The next prime is 20430071. The reversal of 20430057 is 75003402.

It is a happy number.

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.

It is not a de Polignac number, because 20430057 - 2⁴ = 20430041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20430077) 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, 3405007 + ... + 3405012.

It is an arithmetic number, because the mean of its divisors is an integer number (6810020).

Almost surely, 2^20430057 is an apocalyptic number.

It is an amenable number.

20430057 is a deficient number, since it is larger than the sum of its proper divisors (6810023).

20430057 is an equidigital number, since it uses as much as digits as its factorization.

20430057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6810022.

The product of its (nonzero) digits is 840, while the sum is 21.

The square root of 20430057 is about 4519.9620573629. The cubic root of 20430057 is about 273.3735711468.

Adding to 20430057 its reverse (75003402), we get a palindrome (95433459).

The spelling of 20430057 in words is "twenty million, four hundred thirty thousand, fifty-seven".