1999809137456 has 40 divisors (see below), whose sum is σ = 4307281233024. Its totient is φ = 893214996480.

The previous prime is 1999809137429. The next prime is 1999809137467. The reversal of 1999809137456 is 6547319089991.

It is a self number, because there is not a number n which added to its sum of digits gives 1999809137456.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155065601 + ... + 155078496.

Almost surely, 2^{1999809137456} is an apocalyptic number.

1999809137456 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1999809137456 is an abundant number, since it is smaller than the sum of its proper divisors (2307472095568).

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

1999809137456 is a wasteful number, since it uses less digits than its factorization.

1999809137456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310144149 (or 310144143 counting only the distinct ones).

The product of its (nonzero) digits is 132269760, while the sum is 71.

The spelling of 1999809137456 in words is "one trillion, nine hundred ninety-nine billion, eight hundred nine million, one hundred thirty-seven thousand, four hundred fifty-six".