1815895664822 has 4 divisors (see below), whose sum is σ = 2723843497236. Its totient is φ = 907947832410.

The previous prime is 1815895664789. The next prime is 1815895664873. The reversal of 1815895664822 is 2284665985181.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 453973916204 + ... + 453973916207.

It is an arithmetic number, because the mean of its divisors is an integer number (680960874309).

Almost surely, 2^{1815895664822} is an apocalyptic number.

1815895664822 is a deficient number, since it is larger than the sum of its proper divisors (907947832414).

1815895664822 is an equidigital number, since it uses as much as digits as its factorization.

1815895664822 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 907947832413.

The product of its digits is 66355200, while the sum is 65.

The spelling of 1815895664822 in words is "one trillion, eight hundred fifteen billion, eight hundred ninety-five million, six hundred sixty-four thousand, eight hundred twenty-two".