1640805799856 has 20 divisors (see below), whose sum is σ = 3185589098832. Its totient is φ = 818718290496.

The previous prime is 1640805799849. The next prime is 1640805799873. The reversal of 1640805799856 is 6589975080461.

It is a happy number.

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, 105280055 + ... + 105295638.

Almost surely, 2^{1640805799856} is an apocalyptic number.

1640805799856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1640805799856 is a deficient number, since it is larger than the sum of its proper divisors (1544783298976).

1640805799856 is a wasteful number, since it uses less digits than its factorization.

1640805799856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210576188 (or 210576182 counting only the distinct ones).

The product of its (nonzero) digits is 130636800, while the sum is 68.

The spelling of 1640805799856 in words is "one trillion, six hundred forty billion, eight hundred five million, seven hundred ninety-nine thousand, eight hundred fifty-six".