2102021191 has 4 divisors (see below), whose sum is σ = 2122833384. Its totient is φ = 2081209000.

The previous prime is 2102021189. The next prime is 2102021209. The reversal of 2102021191 is 1911202012.

It is a happy number.

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 2102021191 - 2¹ = 2102021189 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 (2102021111) 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, 10405945 + ... + 10406146.

It is an arithmetic number, because the mean of its divisors is an integer number (530708346).

Almost surely, 2^2102021191 is an apocalyptic number.

2102021191 is a deficient number, since it is larger than the sum of its proper divisors (20812193).

2102021191 is a wasteful number, since it uses less digits than its factorization.

2102021191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20812192.

The product of its (nonzero) digits is 72, while the sum is 19.

The square root of 2102021191 is about 45847.8046475510. The cubic root of 2102021191 is about 1280.9898737398.

The spelling of 2102021191 in words is "two billion, one hundred two million, twenty-one thousand, one hundred ninety-one".