20406512 has 20 divisors (see below), whose sum is σ = 45186096. Its totient is φ = 8745600.

The previous prime is 20406461. The next prime is 20406521. The reversal of 20406512 is 21560402.

It is a happy number.

It is a super-2 number, since 2×20406512² = 832851464012288, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90989 + ... + 91212.

Almost surely, 2^20406512 is an apocalyptic number.

It is an amenable number.

20406512 is an abundant number, since it is smaller than the sum of its proper divisors (24779584).

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

20406512 is a wasteful number, since it uses less digits than its factorization.

20406512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182216 (or 182210 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 20406512 is about 4517.3567492506. The cubic root of 20406512 is about 273.2685126216.

Adding to 20406512 its reverse (21560402), we get a palindrome (41966914).

The spelling of 20406512 in words is "twenty million, four hundred six thousand, five hundred twelve".