2191813451 has 8 divisors (see below), whose sum is σ = 2421645984. Its totient is φ = 1973192320.

The previous prime is 2191813447. The next prime is 2191813489. The reversal of 2191813451 is 1543181912.

It is a happy number.

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 2191813451 - 2² = 2191813447 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2191813751) 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, 2802440 + ... + 2803221.

It is an arithmetic number, because the mean of its divisors is an integer number (302705748).

Almost surely, 2^2191813451 is an apocalyptic number.

2191813451 is a deficient number, since it is larger than the sum of its proper divisors (229832533).

2191813451 is a wasteful number, since it uses less digits than its factorization.

2191813451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5605701.

The product of its digits is 8640, while the sum is 35.

The square root of 2191813451 is about 46816.8073559058. The cubic root of 2191813451 is about 1298.9762059707.

The spelling of 2191813451 in words is "two billion, one hundred ninety-one million, eight hundred thirteen thousand, four hundred fifty-one".