21154347173 has 8 divisors (see below), whose sum is σ = 21302344416. Its totient is φ = 21006572400.

The previous prime is 21154347161. The next prime is 21154347187. The reversal of 21154347173 is 37174345112.

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 21154347173 - 2²⁰ = 21153298597 is a prime.

It is a super-3 number, since 3×21154347173³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21154347113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137558 + ... + 247448.

It is an arithmetic number, because the mean of its divisors is an integer number (2662793052).

Almost surely, 2^21154347173 is an apocalyptic number.

It is an amenable number.

21154347173 is a deficient number, since it is larger than the sum of its proper divisors (147997243).

21154347173 is a wasteful number, since it uses less digits than its factorization.

21154347173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111235.

The product of its digits is 70560, while the sum is 38.

The spelling of 21154347173 in words is "twenty-one billion, one hundred fifty-four million, three hundred forty-seven thousand, one hundred seventy-three".