21236242033 has 4 divisors (see below), whose sum is σ = 22159556928. Its totient is φ = 20312927140.

The previous prime is 21236241989. The next prime is 21236242037. The reversal of 21236242033 is 33024263212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21236242033 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21236241992 and 21236242010.

It is not an unprimeable number, because it can be changed into a prime (21236242037) 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 in 3 ways as a sum of consecutive naturals, for example, 461657413 + ... + 461657458.

It is an arithmetic number, because the mean of its divisors is an integer number (5539889232).

Almost surely, 2^21236242033 is an apocalyptic number.

21236242033 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21236242033 is a deficient number, since it is larger than the sum of its proper divisors (923314895).

21236242033 is an equidigital number, since it uses as much as digits as its factorization.

21236242033 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 923314894.

The product of its (nonzero) digits is 10368, while the sum is 28.

The spelling of 21236242033 in words is "twenty-one billion, two hundred thirty-six million, two hundred forty-two thousand, thirty-three".