20857201 has 4 divisors (see below), whose sum is σ = 21041892. Its totient is φ = 20672512.

The previous prime is 20857183. The next prime is 20857211. The reversal of 20857201 is 10275802.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1488400 + 19368801 = 1220^2 + 4401^2 .

It is a cyclic number.

It is not a de Polignac number, because 20857201 - 2⁷ = 20857073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20857211) 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, 92176 + ... + 92401.

It is an arithmetic number, because the mean of its divisors is an integer number (5260473).

Almost surely, 2^20857201 is an apocalyptic number.

It is an amenable number.

20857201 is a deficient number, since it is larger than the sum of its proper divisors (184691).

20857201 is a wasteful number, since it uses less digits than its factorization.

20857201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184690.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 20857201 is about 4566.9684693459. The cubic root of 20857201 is about 275.2656430374.

The spelling of 20857201 in words is "twenty million, eight hundred fifty-seven thousand, two hundred one".