28156351815648 has 1536 divisors, whose sum is σ = 104843870208000. Its totient is φ = 7174513336320.

The previous prime is 28156351815643. The next prime is 28156351815659. The reversal of 28156351815648 is 84651815365182.

28156351815648 is a `hidden beast` number, since 2 + 8 + 1 + 5 + 63 + 5 + 1 + 8 + 1 + 564 + 8 = 666.

It is a super-3 number, since 3×28156351815648³ (a number of 41 digits) contains 333 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28156351815643) by changing a digit.

It is a polite number, since it can be written in 255 ways as a sum of consecutive naturals, for example, 17391198583 + ... + 17391200201.

It is an arithmetic number, because the mean of its divisors is an integer number (68257728000).

Almost surely, 2^{28156351815648} is an apocalyptic number.

28156351815648 is a gapful number since it is divisible by the number (28) 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 28156351815648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52421935104000).

28156351815648 is an abundant number, since it is smaller than the sum of its proper divisors (76687518392352).

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

28156351815648 is a wasteful number, since it uses less digits than its factorization.

28156351815648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1845 (or 1831 counting only the distinct ones).

The product of its digits is 55296000, while the sum is 63.

The spelling of 28156351815648 in words is "twenty-eight trillion, one hundred fifty-six billion, three hundred fifty-one million, eight hundred fifteen thousand, six hundred forty-eight".