20542266 has 72 divisors (see below), whose sum is σ = 48915360. Its totient is φ = 6216672.

The previous prime is 20542259. The next prime is 20542283. The reversal of 20542266 is 66224502.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 348145 + ... + 348203.

It is an arithmetic number, because the mean of its divisors is an integer number (679380).

Almost surely, 2^20542266 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20542266, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24457680).

20542266 is an abundant number, since it is smaller than the sum of its proper divisors (28373094).

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

20542266 is a wasteful number, since it uses less digits than its factorization.

20542266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148 (or 116 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 20542266 is about 4532.3576646156. The cubic root of 20542266 is about 273.8731453209.

Adding to 20542266 its reverse (66224502), we get a palindrome (86766768).

The spelling of 20542266 in words is "twenty million, five hundred forty-two thousand, two hundred sixty-six".