20928554 has 4 divisors (see below), whose sum is σ = 31392834. Its totient is φ = 10464276.

The previous prime is 20928541. The next prime is 20928629. The reversal of 20928554 is 45582902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 45582902 = 2 ⋅22791451.

It can be written as a sum of positive squares in only one way, i.e., 20475625 + 452929 = 4525^2 + 673^2 .

It is an unprimeable number.

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, 5232137 + ... + 5232140.

Almost surely, 2^20928554 is an apocalyptic number.

20928554 is a deficient number, since it is larger than the sum of its proper divisors (10464280).

20928554 is a wasteful number, since it uses less digits than its factorization.

20928554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10464279.

The product of its (nonzero) digits is 28800, while the sum is 35.

The square root of 20928554 is about 4574.7736556031. The cubic root of 20928554 is about 275.5791826221.

The spelling of 20928554 in words is "twenty million, nine hundred twenty-eight thousand, five hundred fifty-four".