21771071173 has 8 divisors (see below), whose sum is σ = 22530166560. Its totient is φ = 21020959440.

The previous prime is 21771071171. The next prime is 21771071177. The reversal of 21771071173 is 37117017712.

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 21771071173 - 2¹ = 21771071171 is a prime.

It is a super-3 number, since 3×21771071173³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21771071171) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2240983 + ... + 2250676.

It is an arithmetic number, because the mean of its divisors is an integer number (2816270820).

Almost surely, 2^21771071173 is an apocalyptic number.

It is an amenable number.

21771071173 is a deficient number, since it is larger than the sum of its proper divisors (759095387).

21771071173 is a wasteful number, since it uses less digits than its factorization.

21771071173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4491827.

The product of its (nonzero) digits is 14406, while the sum is 37.

Adding to 21771071173 its reverse (37117017712), we get a palindrome (58888088885).

The spelling of 21771071173 in words is "twenty-one billion, seven hundred seventy-one million, seventy-one thousand, one hundred seventy-three".