19821328451 has 8 divisors (see below), whose sum is σ = 19861120464. Its totient is φ = 19781578080.

The previous prime is 19821328433. The next prime is 19821328459. The reversal of 19821328451 is 15482312891.

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 19821328451 - 2¹⁴ = 19821312067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19821328459) 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 7 ways as a sum of consecutive naturals, for example, 1047365 + ... + 1066121.

It is an arithmetic number, because the mean of its divisors is an integer number (2482640058).

Almost surely, 2^19821328451 is an apocalyptic number.

19821328451 is a deficient number, since it is larger than the sum of its proper divisors (39792013).

19821328451 is a wasteful number, since it uses less digits than its factorization.

19821328451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20821.

The product of its digits is 138240, while the sum is 44.

The spelling of 19821328451 in words is "nineteen billion, eight hundred twenty-one million, three hundred twenty-eight thousand, four hundred fifty-one".