19921945005 has 16 divisors (see below), whose sum is σ = 35416791360. Its totient is φ = 10625037264.

The previous prime is 19921944953. The next prime is 19921945019. The reversal of 19921945005 is 50054912991.

19921945005 is a `hidden beast` number, since 199 + 2 + 1 + 9 + 450 + 0 + 5 = 666.

It is not a de Polignac number, because 19921945005 - 2⁶ = 19921944941 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 73784847 + ... + 73785116.

It is an arithmetic number, because the mean of its divisors is an integer number (2213549460).

Almost surely, 2^19921945005 is an apocalyptic number.

19921945005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19921945005 is a deficient number, since it is larger than the sum of its proper divisors (15494846355).

19921945005 is a wasteful number, since it uses less digits than its factorization.

19921945005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147569977 (or 147569971 counting only the distinct ones).

The product of its (nonzero) digits is 145800, while the sum is 45.

The spelling of 19921945005 in words is "nineteen billion, nine hundred twenty-one million, nine hundred forty-five thousand, five".