3812891091 has 4 divisors (see below), whose sum is σ = 5083854792. Its totient is φ = 2541927392.

The previous prime is 3812891081. The next prime is 3812891099. The reversal of 3812891091 is 1901982183.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1901982183 = 3 ⋅633994061.

It is a cyclic number.

It is not a de Polignac number, because 3812891091 - 2⁵ = 3812891059 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3812891099) 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, 635481846 + ... + 635481851.

It is an arithmetic number, because the mean of its divisors is an integer number (1270963698).

Almost surely, 2^3812891091 is an apocalyptic number.

3812891091 is a deficient number, since it is larger than the sum of its proper divisors (1270963701).

3812891091 is a wasteful number, since it uses less digits than its factorization.

3812891091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1270963700.

The product of its (nonzero) digits is 31104, while the sum is 42.

The square root of 3812891091 is about 61748.6120572762. The cubic root of 3812891091 is about 1562.2533580273.

The spelling of 3812891091 in words is "three billion, eight hundred twelve million, eight hundred ninety-one thousand, ninety-one".