1897165813 has 4 divisors (see below), whose sum is σ = 2008763820. Its totient is φ = 1785567808.

The previous prime is 1897165783. The next prime is 1897165849. The reversal of 1897165813 is 3185617981.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 856264644 + 1040901169 = 29262^2 + 32263^2 .

It is a cyclic number.

It is not a de Polignac number, because 1897165813 - 2⁹ = 1897165301 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 (1897165883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55798978 + ... + 55799011.

It is an arithmetic number, because the mean of its divisors is an integer number (502190955).

Almost surely, 2^1897165813 is an apocalyptic number.

It is an amenable number.

1897165813 is a deficient number, since it is larger than the sum of its proper divisors (111598007).

1897165813 is a wasteful number, since it uses less digits than its factorization.

1897165813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111598006.

The product of its digits is 362880, while the sum is 49.

The square root of 1897165813 is about 43556.4669480894. The cubic root of 1897165813 is about 1237.9461780299.

The spelling of 1897165813 in words is "one billion, eight hundred ninety-seven million, one hundred sixty-five thousand, eight hundred thirteen".