21002983 has 2 divisors, whose sum is σ = 21002984. Its totient is φ = 21002982.

The previous prime is 21002981. The next prime is 21002987. The reversal of 21002983 is 38920012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21002983 - 2¹ = 21002981 is a prime.

It is a super-2 number, since 2×21002983² = 882250589796578, which contains 22 as substring.

Together with 21002981, 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 (21002981) 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, 10501491 + 10501492.

It is an arithmetic number, because the mean of its divisors is an integer number (10501492).

Almost surely, 2^21002983 is an apocalyptic number.

21002983 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002983 is an equidigital number, since it uses as much as digits as its factorization.

21002983 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 21002983 is about 4582.9011553818. The cubic root of 21002983 is about 275.9054803066.

Adding to 21002983 its reverse (38920012), we get a palindrome (59922995).

The spelling of 21002983 in words is "twenty-one million, two thousand, nine hundred eighty-three".