13538497728 has 672 divisors, whose sum is σ = 47534169600. Its totient is φ = 3372171264.

The previous prime is 13538497697. The next prime is 13538497733. The reversal of 13538497728 is 82779483531.

It is a tau number, because it is divible by the number of its divisors (672).

It is a super-2 number, since 2×13538497728² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (57).

Its product of digits (10160640) is a multiple of the sum of its prime divisors (180).

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, 152117908 + ... + 152117996.

Almost surely, 2^13538497728 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 13538497728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23767084800).

13538497728 is an abundant number, since it is smaller than the sum of its proper divisors (33995671872).

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

13538497728 is a wasteful number, since it uses less digits than its factorization.

13538497728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197 (or 180 counting only the distinct ones).

The product of its digits is 10160640, while the sum is 57.

The spelling of 13538497728 in words is "thirteen billion, five hundred thirty-eight million, four hundred ninety-seven thousand, seven hundred twenty-eight".