1722191 has 2 divisors, whose sum is σ = 1722192. Its totient is φ = 1722190.

The previous prime is 1722187. The next prime is 1722199. The reversal of 1722191 is 1912271.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1722191 - 2² = 1722187 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1722199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 861095 + 861096.

It is an arithmetic number, because the mean of its divisors is an integer number (861096).

2^1722191 is an apocalyptic number.

1722191 is a deficient number, since it is larger than the sum of its proper divisors (1).

1722191 is an equidigital number, since it uses as much as digits as its factorization.

1722191 is an evil number, because the sum of its binary digits is even.

The product of its digits is 252, while the sum is 23.

The square root of 1722191 is about 1312.3227499362. The cubic root of 1722191 is about 119.8653814459.

The spelling of 1722191 in words is "one million, seven hundred twenty-two thousand, one hundred ninety-one".