20628136 has 8 divisors (see below), whose sum is σ = 38677770. Its totient is φ = 10314064.

The previous prime is 20628103. The next prime is 20628137. The reversal of 20628136 is 63182602.

It can be written as a sum of positive squares in only one way, i.e., 18922500 + 1705636 = 4350^2 + 1306^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-3 number, since 3×20628136³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (20628137) 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 as a sum of consecutive naturals, namely, 1289251 + ... + 1289266.

Almost surely, 2^20628136 is an apocalyptic number.

It is an amenable number.

20628136 is a deficient number, since it is larger than the sum of its proper divisors (18049634).

20628136 is a wasteful number, since it uses less digits than its factorization.

20628136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2578523 (or 2578519 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 20628136 is about 4541.8207802598. The cubic root of 20628136 is about 274.2542261927.

The spelling of 20628136 in words is "twenty million, six hundred twenty-eight thousand, one hundred thirty-six".