21033788613 has 4 divisors (see below), whose sum is σ = 28045051488. Its totient is φ = 14022525740.

The previous prime is 21033788609. The next prime is 21033788647. The reversal of 21033788613 is 31688733012.

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 not a de Polignac number, because 21033788613 - 2² = 21033788609 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21033788813) 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 3 ways as a sum of consecutive naturals, for example, 3505631433 + ... + 3505631438.

It is an arithmetic number, because the mean of its divisors is an integer number (7011262872).

Almost surely, 2^21033788613 is an apocalyptic number.

It is an amenable number.

21033788613 is a deficient number, since it is larger than the sum of its proper divisors (7011262875).

21033788613 is an equidigital number, since it uses as much as digits as its factorization.

21033788613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7011262874.

The product of its (nonzero) digits is 145152, while the sum is 42.

The spelling of 21033788613 in words is "twenty-one billion, thirty-three million, seven hundred eighty-eight thousand, six hundred thirteen".