99999999991604 has 24 divisors (see below), whose sum is σ = 175297124287488. Its totient is φ = 49915176504480.

The previous prime is 99999999991589. The next prime is 99999999991621. The reversal of 99999999991604 is 40619999999999.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 99999999991495 and 99999999991504.

It is a congruent number.

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, 2860607 + ... + 14428550.

It is an arithmetic number, because the mean of its divisors is an integer number (7304046845312).

Almost surely, 2^{99999999991604} is an apocalyptic number.

It is an amenable number.

99999999991604 is a deficient number, since it is larger than the sum of its proper divisors (75297124295884).

99999999991604 is a wasteful number, since it uses less digits than its factorization.

99999999991604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17291615 (or 17291613 counting only the distinct ones).

The product of its (nonzero) digits is 83682825624, while the sum is 101.

The spelling of 99999999991604 in words is "ninety-nine trillion, nine hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-one thousand, six hundred four".