20600557 has 4 divisors (see below), whose sum is σ = 20908096. Its totient is φ = 20293020.

The previous prime is 20600551. The next prime is 20600561. The reversal of 20600557 is 75500602.

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, and also an emirpimes, since its reverse is a distinct semiprime: 75500602 = 2 ⋅37750301.

It is a cyclic number.

It is not a de Polignac number, because 20600557 - 2²³ = 12211949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20600551) 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, 153669 + ... + 153802.

It is an arithmetic number, because the mean of its divisors is an integer number (5227024).

Almost surely, 2^20600557 is an apocalyptic number.

It is an amenable number.

20600557 is a deficient number, since it is larger than the sum of its proper divisors (307539).

20600557 is an equidigital number, since it uses as much as digits as its factorization.

20600557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307538.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 20600557 is about 4538.7836476307. The cubic root of 20600557 is about 274.1319493410.

The spelling of 20600557 in words is "twenty million, six hundred thousand, five hundred fifty-seven".