21396434005 has 8 divisors (see below), whose sum is σ = 27186057432. Its totient is φ = 16110256128.

The previous prime is 21396433991. The next prime is 21396434047. The reversal of 21396434005 is 50043469312.

It can be written as a sum of positive squares in 4 ways, for example, as 180472356 + 21215961649 = 13434^2 + 145657^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21396434005 - 2⁵ = 21396433973 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, 125861292 + ... + 125861461.

It is an arithmetic number, because the mean of its divisors is an integer number (3398257179).

Almost surely, 2^21396434005 is an apocalyptic number.

It is an amenable number.

21396434005 is a deficient number, since it is larger than the sum of its proper divisors (5789623427).

21396434005 is a wasteful number, since it uses less digits than its factorization.

21396434005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 251722775.

The product of its (nonzero) digits is 77760, while the sum is 37.

The spelling of 21396434005 in words is "twenty-one billion, three hundred ninety-six million, four hundred thirty-four thousand, five".