19921212523 has 4 divisors (see below), whose sum is σ = 19922167080. Its totient is φ = 19920257968.

The previous prime is 19921212503. The next prime is 19921212533. The reversal of 19921212523 is 32521212991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32521212991 = 19 ⋅1711642789.

It is a cyclic number.

It is not a de Polignac number, because 19921212523 - 2⁹ = 19921212011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19921212503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 445258 + ... + 487951.

It is an arithmetic number, because the mean of its divisors is an integer number (4980541770).

Almost surely, 2^19921212523 is an apocalyptic number.

19921212523 is a deficient number, since it is larger than the sum of its proper divisors (954557).

19921212523 is an equidigital number, since it uses as much as digits as its factorization.

19921212523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 954556.

The product of its digits is 19440, while the sum is 37.

The spelling of 19921212523 in words is "nineteen billion, nine hundred twenty-one million, two hundred twelve thousand, five hundred twenty-three".