20645104 has 10 divisors (see below), whose sum is σ = 39999920. Its totient is φ = 10322544.

The previous prime is 20645083. The next prime is 20645111. The reversal of 20645104 is 40154602.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 645144 + ... + 645175.

It is an arithmetic number, because the mean of its divisors is an integer number (3999992).

Almost surely, 2^20645104 is an apocalyptic number.

It is an amenable number.

20645104 is a deficient number, since it is larger than the sum of its proper divisors (19354816).

20645104 is a wasteful number, since it uses less digits than its factorization.

20645104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1290327 (or 1290321 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 20645104 is about 4543.6883695958. The cubic root of 20645104 is about 274.3294029697.

Adding to 20645104 its reverse (40154602), we get a palindrome (60799706).

The spelling of 20645104 in words is "twenty million, six hundred forty-five thousand, one hundred four".