21131983 has 2 divisors, whose sum is σ = 21131984. Its totient is φ = 21131982.

The previous prime is 21131977. The next prime is 21131989. The reversal of 21131983 is 38913112.

It is a balanced prime because it is at equal distance from previous prime (21131977) and next prime (21131989).

It is a cyclic number.

It is not a de Polignac number, because 21131983 - 2⁵ = 21131951 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21131989) by changing a digit.

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, 10565991 + 10565992.

It is an arithmetic number, because the mean of its divisors is an integer number (10565992).

Almost surely, 2^21131983 is an apocalyptic number.

21131983 is a deficient number, since it is larger than the sum of its proper divisors (1).

21131983 is an equidigital number, since it uses as much as digits as its factorization.

21131983 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 28.

The square root of 21131983 is about 4596.9536652005. The cubic root of 21131983 is about 276.4691968428.

It can be divided in two parts, 2113 and 1983, that added together give a 12-th power (4096 = 2¹²).

The spelling of 21131983 in words is "twenty-one million, one hundred thirty-one thousand, nine hundred eighty-three".