21405230712331 has 8 divisors (see below), whose sum is σ = 22096109159424. Its totient is φ = 20714376461160.

The previous prime is 21405230712329. The next prime is 21405230712373. The reversal of 21405230712331 is 13321703250412.

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 21405230712331 - 2¹ = 21405230712329 is a prime.

It is a super-2 number, since 2×21405230712331² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21405230712731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4242535 + ... + 7798048.

It is an arithmetic number, because the mean of its divisors is an integer number (2762013644928).

Almost surely, 2^{21405230712331} is an apocalyptic number.

21405230712331 is a deficient number, since it is larger than the sum of its proper divisors (690878447093).

21405230712331 is a wasteful number, since it uses less digits than its factorization.

21405230712331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12097961.

The product of its (nonzero) digits is 30240, while the sum is 34.

Adding to 21405230712331 its reverse (13321703250412), we get a palindrome (34726933962743).

The spelling of 21405230712331 in words is "twenty-one trillion, four hundred five billion, two hundred thirty million, seven hundred twelve thousand, three hundred thirty-one".