27899989920 has 960 divisors, whose sum is σ = 114653822976. Its totient is φ = 6322821120.

The previous prime is 27899989889. The next prime is 27899989921. The reversal of 27899989920 is 2998999872.

It is a super-2 number, since 2×27899989920² (a number of 22 digits) contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (27899989921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 219684897 + ... + 219685023.

Almost surely, 2^27899989920 is an apocalyptic number.

27899989920 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 27899989920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57326911488).

27899989920 is an abundant number, since it is smaller than the sum of its proper divisors (86753833056).

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

27899989920 is a wasteful number, since it uses less digits than its factorization.

27899989920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255 (or 238 counting only the distinct ones).

The product of its (nonzero) digits is 105815808, while the sum is 72.

The spelling of 27899989920 in words is "twenty-seven billion, eight hundred ninety-nine million, nine hundred eighty-nine thousand, nine hundred twenty".