21346305681 has 8 divisors (see below), whose sum is σ = 29699208000. Its totient is φ = 13612136912.

The previous prime is 21346305653. The next prime is 21346305691. The reversal of 21346305681 is 18650364312.

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 21346305681 - 2¹⁴ = 21346289297 is a prime.

It is a super-2 number, since 2×21346305681² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21346305691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 154683306 + ... + 154683443.

It is an arithmetic number, because the mean of its divisors is an integer number (3712401000).

Almost surely, 2^21346305681 is an apocalyptic number.

It is an amenable number.

21346305681 is a deficient number, since it is larger than the sum of its proper divisors (8352902319).

21346305681 is a wasteful number, since it uses less digits than its factorization.

21346305681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309366775.

The product of its (nonzero) digits is 103680, while the sum is 39.

Adding to 21346305681 its reverse (18650364312), we get a palindrome (39996669993).

The spelling of 21346305681 in words is "twenty-one billion, three hundred forty-six million, three hundred five thousand, six hundred eighty-one".