19653994668 has 576 divisors, whose sum is σ = 64827392000. Its totient is φ = 4610390400.

The previous prime is 19653994667. The next prime is 19653994669. The reversal of 19653994668 is 86649935691.

It is an interprime number because it is at equal distance from previous prime (19653994667) and next prime (19653994669).

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a junction number, because it is equal to n+sod(n) for n = 19653994599 and 19653994608.

It is not an unprimeable number, because it can be changed into a prime (19653994663) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 293343171 + ... + 293343237.

Almost surely, 2^19653994668 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19653994668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32413696000).

19653994668 is an abundant number, since it is smaller than the sum of its proper divisors (45173397332).

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

19653994668 is a wasteful number, since it uses less digits than its factorization.

19653994668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167 (or 140 counting only the distinct ones).

The product of its digits is 75582720, while the sum is 66.

The spelling of 19653994668 in words is "nineteen billion, six hundred fifty-three million, nine hundred ninety-four thousand, six hundred sixty-eight".