20628667 has 4 divisors (see below), whose sum is σ = 21842136. Its totient is φ = 19415200.

The previous prime is 20628659. The next prime is 20628679. The reversal of 20628667 is 76682602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76682602 = 2 ⋅38341301.

It is a cyclic number.

It is not a de Polignac number, because 20628667 - 2³ = 20628659 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20628767) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 606709 + ... + 606742.

It is an arithmetic number, because the mean of its divisors is an integer number (5460534).

Almost surely, 2^20628667 is an apocalyptic number.

20628667 is a deficient number, since it is larger than the sum of its proper divisors (1213469).

20628667 is a wasteful number, since it uses less digits than its factorization.

20628667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1213468.

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 20628667 is about 4541.8792366156. The cubic root of 20628667 is about 274.2565794146.

The spelling of 20628667 in words is "twenty million, six hundred twenty-eight thousand, six hundred sixty-seven".