1640171911 has 4 divisors (see below), whose sum is σ = 1874482192. Its totient is φ = 1405861632.

The previous prime is 1640171899. The next prime is 1640171921. The reversal of 1640171911 is 1191710461.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1191710461 = 19427 ⋅61343.

It is not a de Polignac number, because 1640171911 - 2⁹ = 1640171399 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 (1640171921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117155130 + ... + 117155143.

It is an arithmetic number, because the mean of its divisors is an integer number (468620548).

Almost surely, 2^1640171911 is an apocalyptic number.

1640171911 is a deficient number, since it is larger than the sum of its proper divisors (234310281).

1640171911 is an equidigital number, since it uses as much as digits as its factorization.

1640171911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234310280.

The product of its (nonzero) digits is 1512, while the sum is 31.

The square root of 1640171911 is about 40499.0359267971. The cubic root of 1640171911 is about 1179.3149118638.

The spelling of 1640171911 in words is "one billion, six hundred forty million, one hundred seventy-one thousand, nine hundred eleven".