21283889505 has 16 divisors (see below), whose sum is σ = 34057463040. Its totient is φ = 11350327808.

The previous prime is 21283889503. The next prime is 21283889519. The reversal of 21283889505 is 50598838212.

It is a cyclic number.

It is not a de Polignac number, because 21283889505 - 2¹ = 21283889503 is a prime.

It is a super-2 number, since 2×21283889505² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21283889503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 110584 + ... + 234086.

It is an arithmetic number, because the mean of its divisors is an integer number (2128591440).

Almost surely, 2^21283889505 is an apocalyptic number.

It is an amenable number.

21283889505 is a deficient number, since it is larger than the sum of its proper divisors (12773573535).

21283889505 is a wasteful number, since it uses less digits than its factorization.

21283889505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135000.

The product of its (nonzero) digits is 1382400, while the sum is 51.

The spelling of 21283889505 in words is "twenty-one billion, two hundred eighty-three million, eight hundred eighty-nine thousand, five hundred five".