171648991 has 8 divisors (see below), whose sum is σ = 175824000. Its totient is φ = 167482392.

The previous prime is 171648959. The next prime is 171649013. The reversal of 171648991 is 199846171.

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 171648991 - 2⁵ = 171648959 is a prime.

It is a super-2 number, since 2×171648991² = 58926752222636162, which contains 22 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 (171648901) 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, 63126 + ... + 65788.

It is an arithmetic number, because the mean of its divisors is an integer number (21978000).

Almost surely, 2^171648991 is an apocalyptic number.

171648991 is a deficient number, since it is larger than the sum of its proper divisors (4175009).

171648991 is a wasteful number, since it uses less digits than its factorization.

171648991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4205.

The product of its digits is 108864, while the sum is 46.

The square root of 171648991 is about 13101.4881215837. The cubic root of 171648991 is about 555.7512117359.

The spelling of 171648991 in words is "one hundred seventy-one million, six hundred forty-eight thousand, nine hundred ninety-one".