20857210 has 32 divisors (see below), whose sum is σ = 41306112. Its totient is φ = 7519680.

The previous prime is 20857183. The next prime is 20857211. The reversal of 20857210 is 1275802.

It is not an unprimeable number, because it can be changed into a prime (20857211) 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 15 ways as a sum of consecutive naturals, for example, 13224 + ... + 14716.

It is an arithmetic number, because the mean of its divisors is an integer number (1290816).

Almost surely, 2^20857210 is an apocalyptic number.

20857210 is a deficient number, since it is larger than the sum of its proper divisors (20448902).

20857210 is a wasteful number, since it uses less digits than its factorization.

20857210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1638.

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

The square root of 20857210 is about 4566.9694546822. The cubic root of 20857210 is about 275.2656826303.

The spelling of 20857210 in words is "twenty million, eight hundred fifty-seven thousand, two hundred ten".