20643146 has 8 divisors (see below), whose sum is σ = 31059264. Its totient is φ = 10290060.

The previous prime is 20643143. The next prime is 20643149. The reversal of 20643146 is 64134602.

It is an interprime number because it is at equal distance from previous prime (20643143) and next prime (20643149).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×20643146² = 852278953554632, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20643143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14930 + ... + 16253.

It is an arithmetic number, because the mean of its divisors is an integer number (3882408).

Almost surely, 2^20643146 is an apocalyptic number.

20643146 is a deficient number, since it is larger than the sum of its proper divisors (10416118).

20643146 is a wasteful number, since it uses less digits than its factorization.

20643146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31516.

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 20643146 is about 4543.4729007665. The cubic root of 20643146 is about 274.3207301475.

Adding to 20643146 its reverse (64134602), we get a palindrome (84777748).

The spelling of 20643146 in words is "twenty million, six hundred forty-three thousand, one hundred forty-six".