19947538347264 has 864 divisors, whose sum is σ = 67797118771200. Its totient is φ = 5577585868800.

The previous prime is 19947538347257. The next prime is 19947538347371. The reversal of 19947538347264 is 46274383574991.

19947538347264 is a `hidden beast` number, since 1 + 9 + 9 + 4 + 75 + 3 + 83 + 472 + 6 + 4 = 666.

It is a super-2 number, since 2×19947538347264² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 19947538347192 and 19947538347201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6306523347 + ... + 6306526509.

Almost surely, 2^{19947538347264} 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 19947538347264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33898559385600).

19947538347264 is an abundant number, since it is smaller than the sum of its proper divisors (47849580423936).

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

19947538347264 is a wasteful number, since it uses less digits than its factorization.

19947538347264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3599 (or 3582 counting only the distinct ones).

The product of its digits is 1097349120, while the sum is 72.

The spelling of 19947538347264 in words is "nineteen trillion, nine hundred forty-seven billion, five hundred thirty-eight million, three hundred forty-seven thousand, two hundred sixty-four".