19294396821 has 48 divisors (see below), whose sum is σ = 31995075840. Its totient is φ = 10975668480.

The previous prime is 19294396817. The next prime is 19294396831. The reversal of 19294396821 is 12869349291.

19294396821 is a `hidden beast` number, since 1 + 92 + 94 + 396 + 82 + 1 = 666.

It is not a de Polignac number, because 19294396821 - 2² = 19294396817 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19294396801) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 22619031 + ... + 22619883.

It is an arithmetic number, because the mean of its divisors is an integer number (666564080).

Almost surely, 2^19294396821 is an apocalyptic number.

It is an amenable number.

19294396821 is a deficient number, since it is larger than the sum of its proper divisors (12700679019).

19294396821 is a wasteful number, since it uses less digits than its factorization.

19294396821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2066 (or 2063 counting only the distinct ones).

The product of its digits is 1679616, while the sum is 54.

The spelling of 19294396821 in words is "nineteen billion, two hundred ninety-four million, three hundred ninety-six thousand, eight hundred twenty-one".