206628457 has 4 divisors (see below), whose sum is σ = 236146816. Its totient is φ = 177110100.

The previous prime is 206628379. The next prime is 206628467. The reversal of 206628457 is 754826602.

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: 754826602 = 2 ⋅377413301.

It is a cyclic number.

It is not a de Polignac number, because 206628457 - 2⁷ = 206628329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (206628467) 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, 14759169 + ... + 14759182.

It is an arithmetic number, because the mean of its divisors is an integer number (59036704).

Almost surely, 2^206628457 is an apocalyptic number.

It is an amenable number.

206628457 is a deficient number, since it is larger than the sum of its proper divisors (29518359).

206628457 is an equidigital number, since it uses as much as digits as its factorization.

206628457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29518358.

The product of its (nonzero) digits is 161280, while the sum is 40.

The square root of 206628457 is about 14374.5767589867. The cubic root of 206628457 is about 591.1940359761.

The spelling of 206628457 in words is "two hundred six million, six hundred twenty-eight thousand, four hundred fifty-seven".