20512420 has 12 divisors (see below), whose sum is σ = 43076124. Its totient is φ = 8204960.

The previous prime is 20512411. The next prime is 20512433. The reversal of 20512420 is 2421502.

It can be written as a sum of positive squares in 2 ways, for example, as 2585664 + 17926756 = 1608^2 + 4234^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20512394 and 20512403.

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, 512791 + ... + 512830.

It is an arithmetic number, because the mean of its divisors is an integer number (3589677).

Almost surely, 2^20512420 is an apocalyptic number.

20512420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20512420 is an abundant number, since it is smaller than the sum of its proper divisors (22563704).

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

20512420 is a wasteful number, since it uses less digits than its factorization.

20512420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1025630 (or 1025628 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 16.

The square root of 20512420 is about 4529.0639209444. The cubic root of 20512420 is about 273.7404436382.

Adding to 20512420 its reverse (2421502), we get a palindrome (22933922).

The spelling of 20512420 in words is "twenty million, five hundred twelve thousand, four hundred twenty".