145217191 has 16 divisors (see below), whose sum is σ = 169646400. Its totient is φ = 121724928.

The previous prime is 145217183. The next prime is 145217227. The reversal of 145217191 is 191712541.

It is a cyclic number.

It is not a de Polignac number, because 145217191 - 2³ = 145217183 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145217161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 188455 + ... + 189223.

It is an arithmetic number, because the mean of its divisors is an integer number (10602900).

Almost surely, 2^145217191 is an apocalyptic number.

145217191 is a deficient number, since it is larger than the sum of its proper divisors (24429209).

145217191 is an equidigital number, since it uses as much as digits as its factorization.

145217191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1338.

The product of its digits is 2520, while the sum is 31.

The square root of 145217191 is about 12050.6095696442. The cubic root of 145217191 is about 525.6209625991.

It can be divided in two parts, 14521 and 7191, that added together give a palindrome (21712).

The spelling of 145217191 in words is "one hundred forty-five million, two hundred seventeen thousand, one hundred ninety-one".