28649138918400 has 4224 divisors, whose sum is σ = 144427076075520. Its totient is φ = 5372116992000.

The previous prime is 28649138918371. The next prime is 28649138918401. The reversal of 28649138918400 is 481983194682.

28649138918400 is a `hidden beast` number, since 2 + 8 + 6 + 4 + 9 + 138 + 91 + 8 + 400 = 666.

28649138918400 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (4224).

It is a super-3 number, since 3×28649138918400³ (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 (28649138918401) by changing a digit.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 32518885960 + ... + 32518886840.

Almost surely, 2^{28649138918400} is an apocalyptic number.

28649138918400 is a gapful number since it is divisible by the number (20) 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 28649138918400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72213538037760).

28649138918400 is an abundant number, since it is smaller than the sum of its proper divisors (115777937157120).

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

28649138918400 is a wasteful number, since it uses less digits than its factorization.

28649138918400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 998 (or 969 counting only the distinct ones).

The product of its (nonzero) digits is 23887872, while the sum is 63.

The spelling of 28649138918400 in words is "twenty-eight trillion, six hundred forty-nine billion, one hundred thirty-eight million, nine hundred eighteen thousand, four hundred".