9871571621 has 8 divisors (see below), whose sum is σ = 10140484224. Its totient is φ = 9602770320.

The previous prime is 9871571597. The next prime is 9871571627. The reversal of 9871571621 is 1261751789.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9871571621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9871571627) 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, 171056 + ... + 221366.

It is an arithmetic number, because the mean of its divisors is an integer number (1267560528).

Almost surely, 2^9871571621 is an apocalyptic number.

It is an amenable number.

9871571621 is a deficient number, since it is larger than the sum of its proper divisors (268912603).

9871571621 is a wasteful number, since it uses less digits than its factorization.

9871571621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55651.

The product of its digits is 211680, while the sum is 47.

The square root of 9871571621 is about 99355.7830274615. The cubic root of 9871571621 is about 2145.1719041470.

The spelling of 9871571621 in words is "nine billion, eight hundred seventy-one million, five hundred seventy-one thousand, six hundred twenty-one".