19821965625 has 336 divisors, whose sum is σ = 46722759552. Its totient is φ = 8164800000.

The previous prime is 19821965599. The next prime is 19821965663. The reversal of 19821965625 is 52656912891.

19821965625 is a `hidden beast` number, since 1 + 9 + 8 + 2 + 1 + 9 + 6 + 5 + 625 = 666.

It is not a de Polignac number, because 19821965625 - 2⁸ = 19821965369 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 335 ways as a sum of consecutive naturals, for example, 175415569 + ... + 175415681.

It is an arithmetic number, because the mean of its divisors is an integer number (139055832).

Almost surely, 2^19821965625 is an apocalyptic number.

19821965625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19821965625 is an abundant number, since it is smaller than the sum of its proper divisors (26900793927).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19821965625 is an frugal number, since it uses more digits than its factorization.

19821965625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174 (or 139 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 54.

The spelling of 19821965625 in words is "nineteen billion, eight hundred twenty-one million, nine hundred sixty-five thousand, six hundred twenty-five".