2191501 has 8 divisors (see below), whose sum is σ = 2441880. Its totient is φ = 1952832.

The previous prime is 2191493. The next prime is 2191507. The reversal of 2191501 is 1051912.

It can be written as a sum of positive squares in 4 ways, for example, as 203401 + 1988100 = 451^2 + 1410^2 .

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 2191501 - 2³ = 2191493 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191507) 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, 2530 + ... + 3283.

It is an arithmetic number, because the mean of its divisors is an integer number (305235).

2^2191501 is an apocalyptic number.

It is an amenable number.

2191501 is a deficient number, since it is larger than the sum of its proper divisors (250379).

2191501 is a wasteful number, since it uses less digits than its factorization.

2191501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5855.

The product of its (nonzero) digits is 90, while the sum is 19.

The square root of 2191501 is about 1480.3719127300. The cubic root of 2191501 is about 129.8914478439.

The spelling of 2191501 in words is "two million, one hundred ninety-one thousand, five hundred one".