20975983 has 8 divisors (see below), whose sum is σ = 24210720. Its totient is φ = 17800800.

The previous prime is 20975971. The next prime is 20975987. The reversal of 20975983 is 38957902.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20975983 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20975987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14128 + ... + 15541.

It is an arithmetic number, because the mean of its divisors is an integer number (3026340).

Almost surely, 2^20975983 is an apocalyptic number.

20975983 is a deficient number, since it is larger than the sum of its proper divisors (3234737).

20975983 is a wasteful number, since it uses less digits than its factorization.

20975983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29777.

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 20975983 is about 4579.9544757563. The cubic root of 20975983 is about 275.7872011965.

The spelling of 20975983 in words is "twenty million, nine hundred seventy-five thousand, nine hundred eighty-three".