20724146 has 16 divisors (see below), whose sum is σ = 31558848. Its totient is φ = 10206000.

The previous prime is 20724097. The next prime is 20724161. The reversal of 20724146 is 64142702.

It is a Smith number, since the sum of its digits (26) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49016 + ... + 49436.

It is an arithmetic number, because the mean of its divisors is an integer number (1972428).

Almost surely, 2^20724146 is an apocalyptic number.

20724146 is a deficient number, since it is larger than the sum of its proper divisors (10834702).

20724146 is a wasteful number, since it uses less digits than its factorization.

20724146 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 737.

The product of its (nonzero) digits is 2688, while the sum is 26.

The square root of 20724146 is about 4552.3780598716. The cubic root of 20724146 is about 274.6790569892.

Adding to 20724146 its reverse (64142702), we get a palindrome (84866848).

The spelling of 20724146 in words is "twenty million, seven hundred twenty-four thousand, one hundred forty-six".