1863818197 has 4 divisors (see below), whose sum is σ = 1928087820. Its totient is φ = 1799548576.

The previous prime is 1863818191. The next prime is 1863818207. The reversal of 1863818197 is 7918183681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7918183681 = 127 ⋅62347903.

It can be written as a sum of positive squares in 2 ways, for example, as 508547601 + 1355270596 = 22551^2 + 36814^2 .

It is a cyclic number.

It is not a de Polignac number, because 1863818197 - 2³ = 1863818189 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 (1863818191) 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, 32134768 + ... + 32134825.

It is an arithmetic number, because the mean of its divisors is an integer number (482021955).

Almost surely, 2^1863818197 is an apocalyptic number.

It is an amenable number.

1863818197 is a deficient number, since it is larger than the sum of its proper divisors (64269623).

1863818197 is an equidigital number, since it uses as much as digits as its factorization.

1863818197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64269622.

The product of its digits is 580608, while the sum is 52.

The square root of 1863818197 is about 43171.9607731685. The cubic root of 1863818197 is about 1230.6498861451.

The spelling of 1863818197 in words is "one billion, eight hundred sixty-three million, eight hundred eighteen thousand, one hundred ninety-seven".