20638057 has 4 divisors (see below), whose sum is σ = 22514256. Its totient is φ = 18761860.

The previous prime is 20638043. The next prime is 20638081. The reversal of 20638057 is 75083602.

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 a cyclic number.

It is not a de Polignac number, because 20638057 - 2¹¹ = 20636009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20638087) 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, 938083 + ... + 938104.

It is an arithmetic number, because the mean of its divisors is an integer number (5628564).

Almost surely, 2^20638057 is an apocalyptic number.

It is an amenable number.

20638057 is a deficient number, since it is larger than the sum of its proper divisors (1876199).

20638057 is a wasteful number, since it uses less digits than its factorization.

20638057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1876198.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 20638057 is about 4542.9128320935. The cubic root of 20638057 is about 274.2981862173.

The spelling of 20638057 in words is "twenty million, six hundred thirty-eight thousand, fifty-seven".