20855983 has 2 divisors, whose sum is σ = 20855984. Its totient is φ = 20855982.

The previous prime is 20855981. The next prime is 20855987. The reversal of 20855983 is 38955802.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20855983 - 2¹ = 20855981 is a prime.

Together with 20855981, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20855981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10427991 + 10427992.

It is an arithmetic number, because the mean of its divisors is an integer number (10427992).

Almost surely, 2^20855983 is an apocalyptic number.

20855983 is a deficient number, since it is larger than the sum of its proper divisors (1).

20855983 is an equidigital number, since it uses as much as digits as its factorization.

20855983 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 86400, while the sum is 40.

The square root of 20855983 is about 4566.8351185476. The cubic root of 20855983 is about 275.2602846949.

The spelling of 20855983 in words is "twenty million, eight hundred fifty-five thousand, nine hundred eighty-three".