20643382 has 4 divisors (see below), whose sum is σ = 30965076. Its totient is φ = 10321690.

The previous prime is 20643379. The next prime is 20643407. The reversal of 20643382 is 28334602.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×20643382² = 852298440795848, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20643382.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5160844 + ... + 5160847.

It is an arithmetic number, because the mean of its divisors is an integer number (7741269).

Almost surely, 2^20643382 is an apocalyptic number.

20643382 is a deficient number, since it is larger than the sum of its proper divisors (10321694).

20643382 is a wasteful number, since it uses less digits than its factorization.

20643382 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10321693.

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 20643382 is about 4543.4988720148. The cubic root of 20643382 is about 274.3217755218.

Adding to 20643382 its reverse (28334602), we get a palindrome (48977984).

It can be divided in two parts, 20643 and 382, that added together give a square (21025 = 145²).

The spelling of 20643382 in words is "twenty million, six hundred forty-three thousand, three hundred eighty-two".