19955599920 has 60 divisors (see below), whose sum is σ = 67017558816. Its totient is φ = 5321493120.

The previous prime is 19955599907. The next prime is 19955599969. The reversal of 19955599920 is 2999555991.

19955599920 is a `hidden beast` number, since 19 + 9 + 5 + 5 + 599 + 9 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13857336 + ... + 13858775.

Almost surely, 2^19955599920 is an apocalyptic number.

19955599920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19955599920 is an abundant number, since it is smaller than the sum of its proper divisors (47061958896).

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

19955599920 is a wasteful number, since it uses less digits than its factorization.

19955599920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27716130 (or 27716121 counting only the distinct ones).

The product of its (nonzero) digits is 14762250, while the sum is 63.

The spelling of 19955599920 in words is "nineteen billion, nine hundred fifty-five million, five hundred ninety-nine thousand, nine hundred twenty".