19906429438891 has 8 divisors (see below), whose sum is σ = 19908859815504. Its totient is φ = 19903999245600.

The previous prime is 19906429438873. The next prime is 19906429438897. The reversal of 19906429438891 is 19883492460991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19906429438891 - 2¹¹ = 19906429436843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19906429438897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 377468361 + ... + 377521093.

It is an arithmetic number, because the mean of its divisors is an integer number (2488607476938).

Almost surely, 2^{19906429438891} is an apocalyptic number.

19906429438891 is a deficient number, since it is larger than the sum of its proper divisors (2430376613).

19906429438891 is a wasteful number, since it uses less digits than its factorization.

19906429438891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91661.

The product of its (nonzero) digits is 241864704, while the sum is 73.

The spelling of 19906429438891 in words is "nineteen trillion, nine hundred six billion, four hundred twenty-nine million, four hundred thirty-eight thousand, eight hundred ninety-one".