19777998976 has 64 divisors (see below), whose sum is σ = 40243596120. Its totient is φ = 9678569472.

The previous prime is 19777998973. The next prime is 19777998997. The reversal of 19777998976 is 67989977791.

It can be written as a sum of positive squares in 4 ways, for example, as 19369958976 + 408040000 = 139176^2 + 20200^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a junction number, because it is equal to n+sod(n) for n = 19777998896 and 19777998905.

It is not an unprimeable number, because it can be changed into a prime (19777998973) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2934106 + ... + 2940838.

Almost surely, 2^19777998976 is an apocalyptic number.

19777998976 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 19777998976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20121798060).

19777998976 is an abundant number, since it is smaller than the sum of its proper divisors (20465597144).

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

19777998976 is an equidigital number, since it uses as much as digits as its factorization.

19777998976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7233 (or 7221 counting only the distinct ones).

The product of its digits is 756142128, while the sum is 79.

The spelling of 19777998976 in words is "nineteen billion, seven hundred seventy-seven million, nine hundred ninety-eight thousand, nine hundred seventy-six".