21146543456417 has 4 divisors (see below), whose sum is σ = 21146555653296. Its totient is φ = 21146531259540.

The previous prime is 21146543456369. The next prime is 21146543456443. The reversal of 21146543456417 is 71465434564112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21146543456417 - 2⁸ = 21146543456161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21146543456617) 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 3 ways as a sum of consecutive naturals, for example, 2959103 + ... + 7144884.

It is an arithmetic number, because the mean of its divisors is an integer number (5286638913324).

Almost surely, 2^{21146543456417} is an apocalyptic number.

It is an amenable number.

21146543456417 is a deficient number, since it is larger than the sum of its proper divisors (12196879).

21146543456417 is a wasteful number, since it uses less digits than its factorization.

21146543456417 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12196878.

The product of its digits is 9676800, while the sum is 53.

The spelling of 21146543456417 in words is "twenty-one trillion, one hundred forty-six billion, five hundred forty-three million, four hundred fifty-six thousand, four hundred seventeen".