101173991 has 4 divisors (see below), whose sum is σ = 101195952. Its totient is φ = 101152032.

The previous prime is 101173981. The next prime is 101173997. The reversal of 101173991 is 199371101.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 101173991 - 2⁶ = 101173927 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 (101173997) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1115 + ... + 14268.

It is an arithmetic number, because the mean of its divisors is an integer number (25298988).

Almost surely, 2^101173991 is an apocalyptic number.

101173991 is a deficient number, since it is larger than the sum of its proper divisors (21961).

101173991 is an equidigital number, since it uses as much as digits as its factorization.

101173991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21960.

The product of its (nonzero) digits is 1701, while the sum is 32.

The square root of 101173991 is about 10058.5282720684. The cubic root of 101173991 is about 465.9682157646.

The spelling of 101173991 in words is "one hundred one million, one hundred seventy-three thousand, nine hundred ninety-one".