20215146 has 48 divisors (see below), whose sum is σ = 48673440. Its totient is φ = 5574240.

The previous prime is 20215133. The next prime is 20215147. The reversal of 20215146 is 64151202.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (20215147) 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 23 ways as a sum of consecutive naturals, for example, 7341 + ... + 9711.

It is an arithmetic number, because the mean of its divisors is an integer number (1014030).

Almost surely, 2^20215146 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20215146, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24336720).

20215146 is an abundant number, since it is smaller than the sum of its proper divisors (28458294).

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

20215146 is a wasteful number, since it uses less digits than its factorization.

20215146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2419 (or 2412 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 20215146 is about 4496.1256655036. The cubic root of 20215146 is about 272.4116190671.

Adding to 20215146 its reverse (64151202), we get a palindrome (84366348).

The spelling of 20215146 in words is "twenty million, two hundred fifteen thousand, one hundred forty-six".