20316645 has 12 divisors (see below), whose sum is σ = 35215596. Its totient is φ = 10835520.

The previous prime is 20316641. The next prime is 20316671. The reversal of 20316645 is 54661302.

20316645 is a `hidden beast` number, since 2 + 0 + 3 + 16 + 645 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 8661249 + 11655396 = 2943^2 + 3414^2 .

It is not a de Polignac number, because 20316645 - 2² = 20316641 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20316641) 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 11 ways as a sum of consecutive naturals, for example, 225696 + ... + 225785.

It is an arithmetic number, because the mean of its divisors is an integer number (2934633).

Almost surely, 2^20316645 is an apocalyptic number.

It is an amenable number.

20316645 is a deficient number, since it is larger than the sum of its proper divisors (14898951).

20316645 is a wasteful number, since it uses less digits than its factorization.

20316645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451492 (or 451489 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 20316645 is about 4507.3989173358. The cubic root of 20316645 is about 272.8667787789.

Adding to 20316645 its reverse (54661302), we get a palindrome (74977947).

The spelling of 20316645 in words is "twenty million, three hundred sixteen thousand, six hundred forty-five".