21002136403 has 2 divisors, whose sum is σ = 21002136404. Its totient is φ = 21002136402.

The previous prime is 21002136383. The next prime is 21002136439. The reversal of 21002136403 is 30463120012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21002136403 - 2¹⁷ = 21002005331 is a prime.

It is not a weakly prime, because it can be changed into another prime (21002134403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501068201 + 10501068202.

It is an arithmetic number, because the mean of its divisors is an integer number (10501068202).

Almost surely, 2^21002136403 is an apocalyptic number.

21002136403 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002136403 is an equidigital number, since it uses as much as digits as its factorization.

21002136403 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 22.

Adding to 21002136403 its reverse (30463120012), we get a palindrome (51465256415).

The spelling of 21002136403 in words is "twenty-one billion, two million, one hundred thirty-six thousand, four hundred three".