1818713849661 has 24 divisors (see below), whose sum is σ = 2638137509280. Its totient is φ = 1207352220000.

The previous prime is 1818713849639. The next prime is 1818713849663. The reversal of 1818713849661 is 1669483178181.

1818713849661 is a `hidden beast` number, since 1 + 8 + 1 + 8 + 7 + 138 + 496 + 6 + 1 = 666.

It is not a de Polignac number, because 1818713849661 - 2⁵ = 1818713849629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1818713849663) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9417055 + ... + 9608243.

It is an arithmetic number, because the mean of its divisors is an integer number (109922396220).

Almost surely, 2^{1818713849661} is an apocalyptic number.

It is an amenable number.

1818713849661 is a deficient number, since it is larger than the sum of its proper divisors (819423659619).

1818713849661 is a wasteful number, since it uses less digits than its factorization.

1818713849661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195657 (or 195654 counting only the distinct ones).

The product of its digits is 13934592, while the sum is 63.

The spelling of 1818713849661 in words is "one trillion, eight hundred eighteen billion, seven hundred thirteen million, eight hundred forty-nine thousand, six hundred sixty-one".