19685975400 has 1152 divisors, whose sum is σ = 87275664000. Its totient is φ = 4041031680.

The previous prime is 19685975399. The next prime is 19685975423. The reversal of 19685975400 is 457958691.

19685975400 is a `hidden beast` number, since 1 + 9 + 6 + 8 + 5 + 97 + 540 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 202948152 + ... + 202948248.

It is an arithmetic number, because the mean of its divisors is an integer number (75760125).

Almost surely, 2^19685975400 is an apocalyptic number.

19685975400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19685975400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43637832000).

19685975400 is an abundant number, since it is smaller than the sum of its proper divisors (67589688600).

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

19685975400 is a wasteful number, since it uses less digits than its factorization.

19685975400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208 (or 186 counting only the distinct ones).

The product of its (nonzero) digits is 2721600, while the sum is 54.

The spelling of 19685975400 in words is "nineteen billion, six hundred eighty-five million, nine hundred seventy-five thousand, four hundred".