20904210 has 64 divisors (see below), whose sum is σ = 56246400. Its totient is φ = 5524416.

The previous prime is 20904193. The next prime is 20904227. The reversal of 20904210 is 1240902.

It is an interprime number because it is at equal distance from previous prime (20904193) and next prime (20904227).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37252 + ... + 37808.

It is an arithmetic number, because the mean of its divisors is an integer number (878850).

Almost surely, 2^20904210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20904210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28123200).

20904210 is an abundant number, since it is smaller than the sum of its proper divisors (35342190).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20904210 is a wasteful number, since it uses less digits than its factorization.

20904210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712 (or 706 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 20904210 is about 4572.1122033476. The cubic root of 20904210 is about 275.4722903434.

The spelling of 20904210 in words is "twenty million, nine hundred four thousand, two hundred ten".