21002354005 has 8 divisors (see below), whose sum is σ = 25342068024. Its totient is φ = 16709054400.

The previous prime is 21002353951. The next prime is 21002354063. The reversal of 21002354005 is 50045320012.

It can be written as a sum of positive squares in 4 ways, for example, as 83649316 + 20918704689 = 9146^2 + 144633^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-21002354005 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11602606 + ... + 11604415.

It is an arithmetic number, because the mean of its divisors is an integer number (3167758503).

Almost surely, 2^21002354005 is an apocalyptic number.

It is an amenable number.

21002354005 is a deficient number, since it is larger than the sum of its proper divisors (4339714019).

21002354005 is a wasteful number, since it uses less digits than its factorization.

21002354005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23207207.

The product of its (nonzero) digits is 1200, while the sum is 22.

Adding to 21002354005 its reverse (50045320012), we get a palindrome (71047674017).

The spelling of 21002354005 in words is "twenty-one billion, two million, three hundred fifty-four thousand, five".