20829312 has 240 divisors, whose sum is σ = 73866870. Its totient is φ = 5806080.

The previous prime is 20829269. The next prime is 20829313. The reversal of 20829312 is 21392802.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20575296 + 254016 = 4536^2 + 504^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (20829313) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 508012 + ... + 508052.

Almost surely, 2^20829312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20829312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36933435).

20829312 is an abundant number, since it is smaller than the sum of its proper divisors (53037558).

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

20829312 is an equidigital number, since it uses as much as digits as its factorization.

20829312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 20829312 is about 4563.9141096213. The cubic root of 20829312 is about 275.1428987352.

The spelling of 20829312 in words is "twenty million, eight hundred twenty-nine thousand, three hundred twelve".