21005333699 has 4 divisors (see below), whose sum is σ = 24006095664. Its totient is φ = 18004571736.

The previous prime is 21005333693. The next prime is 21005333743. The reversal of 21005333699 is 99633350012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21005333699 - 2¹² = 21005329603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21005333693) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1500380972 + ... + 1500380985.

It is an arithmetic number, because the mean of its divisors is an integer number (6001523916).

Almost surely, 2^21005333699 is an apocalyptic number.

21005333699 is a deficient number, since it is larger than the sum of its proper divisors (3000761965).

21005333699 is an equidigital number, since it uses as much as digits as its factorization.

21005333699 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3000761964.

The product of its (nonzero) digits is 131220, while the sum is 41.

The spelling of 21005333699 in words is "twenty-one billion, five million, three hundred thirty-three thousand, six hundred ninety-nine".