21287489983 has 2 divisors, whose sum is σ = 21287489984. Its totient is φ = 21287489982.

The previous prime is 21287489969. The next prime is 21287489999. The reversal of 21287489983 is 38998478212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21287489983 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21287489903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10643744991 + 10643744992.

It is an arithmetic number, because the mean of its divisors is an integer number (10643744992).

Almost surely, 2^21287489983 is an apocalyptic number.

21287489983 is a deficient number, since it is larger than the sum of its proper divisors (1).

21287489983 is an equidigital number, since it uses as much as digits as its factorization.

21287489983 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13934592, while the sum is 61.

The spelling of 21287489983 in words is "twenty-one billion, two hundred eighty-seven million, four hundred eighty-nine thousand, nine hundred eighty-three".