20206457 has 4 divisors (see below), whose sum is σ = 20238336. Its totient is φ = 20174580.

The previous prime is 20206453. The next prime is 20206493. The reversal of 20206457 is 75460202.

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: 75460202 = 2 ⋅37730101.

It is a cyclic number.

It is not a de Polignac number, because 20206457 - 2² = 20206453 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20206453) 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 in 3 ways as a sum of consecutive naturals, for example, 14969 + ... + 16262.

It is an arithmetic number, because the mean of its divisors is an integer number (5059584).

Almost surely, 2^20206457 is an apocalyptic number.

It is an amenable number.

20206457 is a deficient number, since it is larger than the sum of its proper divisors (31879).

20206457 is an equidigital number, since it uses as much as digits as its factorization.

20206457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31878.

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 20206457 is about 4495.1592852757. The cubic root of 20206457 is about 272.3725835873.

Adding to 20206457 its reverse (75460202), we get a palindrome (95666659).

The spelling of 20206457 in words is "twenty million, two hundred six thousand, four hundred fifty-seven".