21006622999 has 4 divisors (see below), whose sum is σ = 21013773480. Its totient is φ = 20999472520.

The previous prime is 21006622997. The next prime is 21006623021. The reversal of 21006622999 is 99922660012.

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 21006622999 - 2¹ = 21006622997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21006622993) 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, 3570832 + ... + 3576709.

It is an arithmetic number, because the mean of its divisors is an integer number (5253443370).

Almost surely, 2^21006622999 is an apocalyptic number.

21006622999 is a deficient number, since it is larger than the sum of its proper divisors (7150481).

21006622999 is an equidigital number, since it uses as much as digits as its factorization.

21006622999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7150480.

The product of its (nonzero) digits is 209952, while the sum is 46.

The spelling of 21006622999 in words is "twenty-one billion, six million, six hundred twenty-two thousand, nine hundred ninety-nine".