2191654619 has 32 divisors (see below), whose sum is σ = 2765767680. Its totient is φ = 1687104000.

The previous prime is 2191654601. The next prime is 2191654639. The reversal of 2191654619 is 9164561912.

It is a cyclic number.

It is not a de Polignac number, because 2191654619 - 2²⁴ = 2174877403 is a prime.

It is a super-2 number, since 2×2191654619² = 9606699937968070322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2191654619.

It is not an unprimeable number, because it can be changed into a prime (2191654639) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2708687 + ... + 2709495.

It is an arithmetic number, because the mean of its divisors is an integer number (86430240).

Almost surely, 2^2191654619 is an apocalyptic number.

2191654619 is a deficient number, since it is larger than the sum of its proper divisors (574113061).

2191654619 is a wasteful number, since it uses less digits than its factorization.

2191654619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1211.

The product of its digits is 116640, while the sum is 44.

The square root of 2191654619 is about 46815.1110112963. Note that the first 3 decimals coincide. The cubic root of 2191654619 is about 1298.9448280004.

The spelling of 2191654619 in words is "two billion, one hundred ninety-one million, six hundred fifty-four thousand, six hundred nineteen".