1816339372644 has 12 divisors (see below), whose sum is σ = 4238125202864. Its totient is φ = 605446457544.

The previous prime is 1816339372613. The next prime is 1816339372663. The reversal of 1816339372644 is 4462739336181.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75680807182 + ... + 75680807205.

Almost surely, 2^{1816339372644} is an apocalyptic number.

It is an amenable number.

1816339372644 is an abundant number, since it is smaller than the sum of its proper divisors (2421785830220).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1816339372644 is a wasteful number, since it uses less digits than its factorization.

1816339372644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151361614394 (or 151361614392 counting only the distinct ones).

The product of its digits is 15676416, while the sum is 57.

The spelling of 1816339372644 in words is "one trillion, eight hundred sixteen billion, three hundred thirty-nine million, three hundred seventy-two thousand, six hundred forty-four".