28061611991784 has 576 divisors, whose sum is σ = 94024914984000. Its totient is φ = 7517155000320.

The previous prime is 28061611991717. The next prime is 28061611991789. The reversal of 28061611991784 is 48719911616082.

28061611991784 is a `hidden beast` number, since 2 + 8 + 0 + 6 + 1 + 611 + 9 + 9 + 1 + 7 + 8 + 4 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (28061611991789) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 8424378999 + ... + 8424382329.

It is an arithmetic number, because the mean of its divisors is an integer number (163237699625).

Almost surely, 2^{28061611991784} is an apocalyptic number.

28061611991784 is a gapful number since it is divisible by the number (24) 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 28061611991784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47012457492000).

28061611991784 is an abundant number, since it is smaller than the sum of its proper divisors (65963302992216).

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

28061611991784 is a wasteful number, since it uses less digits than its factorization.

28061611991784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4638 (or 4624 counting only the distinct ones).

The product of its (nonzero) digits is 10450944, while the sum is 63.

The spelling of 28061611991784 in words is "twenty-eight trillion, sixty-one billion, six hundred eleven million, nine hundred ninety-one thousand, seven hundred eighty-four".