19988470656 has 512 divisors, whose sum is σ = 75954585600. Its totient is φ = 5022259200.

The previous prime is 19988470639. The next prime is 19988470657. The reversal of 19988470656 is 65607488991.

19988470656 is a `hidden beast` number, since 19 + 98 + 8 + 470 + 65 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 19988470593 and 19988470602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19988470657) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8248261 + ... + 8250683.

It is an arithmetic number, because the mean of its divisors is an integer number (148348800).

Almost surely, 2^19988470656 is an apocalyptic number.

19988470656 is a gapful number since it is divisible by the number (16) 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 19988470656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37977292800).

19988470656 is an abundant number, since it is smaller than the sum of its proper divisors (55966114944).

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

19988470656 is a wasteful number, since it uses less digits than its factorization.

19988470656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2495 (or 2477 counting only the distinct ones).

The product of its (nonzero) digits is 26127360, while the sum is 63.

The spelling of 19988470656 in words is "nineteen billion, nine hundred eighty-eight million, four hundred seventy thousand, six hundred fifty-six".