21346352729 has 16 divisors (see below), whose sum is σ = 23225564544. Its totient is φ = 19501257600.

The previous prime is 21346352711. The next prime is 21346352767. The reversal of 21346352729 is 92725364312.

It is a cyclic number.

It is not a de Polignac number, because 21346352729 - 2³² = 17051385433 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21346352729.

It is not an unprimeable number, because it can be changed into a prime (21346352779) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2849669 + ... + 2857149.

It is an arithmetic number, because the mean of its divisors is an integer number (1451597784).

Almost surely, 2^21346352729 is an apocalyptic number.

It is an amenable number.

21346352729 is a deficient number, since it is larger than the sum of its proper divisors (1879211815).

21346352729 is a wasteful number, since it uses less digits than its factorization.

21346352729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9728.

The product of its digits is 544320, while the sum is 44.

The spelling of 21346352729 in words is "twenty-one billion, three hundred forty-six million, three hundred fifty-two thousand, seven hundred twenty-nine".