1999899415684 has 81 divisors (see below), whose sum is σ = 3719451507429. Its totient is φ = 940824339840.

The previous prime is 1999899415673. The next prime is 1999899415727. The reversal of 1999899415684 is 4865149989991.

The square root of 1999899415684 is 1414178.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 224268544900 + 1775630870784 = 473570^2 + 1332528^2 .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1999899415598 and 1999899415607.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 4618705132 + ... + 4618705564.

Almost surely, 2^{1999899415684} is an apocalyptic number.

1999899415684 is the 1414178-th square number.

It is an amenable number.

1999899415684 is a deficient number, since it is larger than the sum of its proper divisors (1719552091745).

1999899415684 is an frugal number, since it uses more digits than its factorization.

1999899415684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1058 (or 529 counting only the distinct ones).

The product of its digits is 1813985280, while the sum is 82.

The spelling of 1999899415684 in words is "one trillion, nine hundred ninety-nine billion, eight hundred ninety-nine million, four hundred fifteen thousand, six hundred eighty-four".