2191423009 has 2 divisors, whose sum is σ = 2191423010. Its totient is φ = 2191423008.

The previous prime is 2191422991. The next prime is 2191423099. The reversal of 2191423009 is 9003241912.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2118576784 + 72846225 = 46028^2 + 8535^2 .

It is a cyclic number.

It is not a de Polignac number, because 2191423009 - 2⁵ = 2191422977 is a prime.

It is a super-2 number, since 2×2191423009² = 9604669608749228162, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2191423099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1095711504 + 1095711505.

It is an arithmetic number, because the mean of its divisors is an integer number (1095711505).

Almost surely, 2^2191423009 is an apocalyptic number.

It is an amenable number.

2191423009 is a deficient number, since it is larger than the sum of its proper divisors (1).

2191423009 is an equidigital number, since it uses as much as digits as its factorization.

2191423009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 2191423009 is about 46812.6372788374. The cubic root of 2191423009 is about 1298.8990696941.

The spelling of 2191423009 in words is "two billion, one hundred ninety-one million, four hundred twenty-three thousand, nine".