20929943 has 4 divisors (see below), whose sum is σ = 21055440. Its totient is φ = 20804448.

The previous prime is 20929939. The next prime is 20929957. The reversal of 20929943 is 34992902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20929943 - 2² = 20929939 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20929897 and 20929906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20929543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 62498 + ... + 62831.

It is an arithmetic number, because the mean of its divisors is an integer number (5263860).

Almost surely, 2^20929943 is an apocalyptic number.

20929943 is a deficient number, since it is larger than the sum of its proper divisors (125497).

20929943 is a wasteful number, since it uses less digits than its factorization.

20929943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125496.

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 20929943 is about 4574.9254638737. The cubic root of 20929943 is about 275.5852790939.

The spelling of 20929943 in words is "twenty million, nine hundred twenty-nine thousand, nine hundred forty-three".