20628404 has 6 divisors (see below), whose sum is σ = 36099714. Its totient is φ = 10314200.

The previous prime is 20628403. The next prime is 20628409. The reversal of 20628404 is 40482602.

It can be written as a sum of positive squares in only one way, i.e., 17205904 + 3422500 = 4148^2 + 1850^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20628403) by changing a digit.

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 as a sum of consecutive naturals, namely, 2578547 + ... + 2578554.

It is an arithmetic number, because the mean of its divisors is an integer number (6016619).

Almost surely, 2^20628404 is an apocalyptic number.

It is an amenable number.

20628404 is a deficient number, since it is larger than the sum of its proper divisors (15471310).

20628404 is a wasteful number, since it uses less digits than its factorization.

20628404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5157105 (or 5157103 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 26.

The square root of 20628404 is about 4541.8502837500. The cubic root of 20628404 is about 274.2554138879.

The spelling of 20628404 in words is "twenty million, six hundred twenty-eight thousand, four hundred four".