191161021 has 8 divisors (see below), whose sum is σ = 193474080. Its totient is φ = 188862192.

The previous prime is 191160979. The next prime is 191161031. The reversal of 191161021 is 120161191.

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 191161021 - 2⁹ = 191160509 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 191160983 and 191161001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (191161031) 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, 24810 + ... + 31588.

It is an arithmetic number, because the mean of its divisors is an integer number (24184260).

Almost surely, 2^191161021 is an apocalyptic number.

It is an amenable number.

191161021 is a deficient number, since it is larger than the sum of its proper divisors (2313059).

191161021 is a wasteful number, since it uses less digits than its factorization.

191161021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7115.

The product of its (nonzero) digits is 108, while the sum is 22.

The square root of 191161021 is about 13826.0992691359. The cubic root of 191161021 is about 576.0583115558.

The spelling of 191161021 in words is "one hundred ninety-one million, one hundred sixty-one thousand, twenty-one".