28187267400 has 144 divisors (see below), whose sum is σ = 94811158260. Its totient is φ = 7504780800.

The previous prime is 28187267393. The next prime is 28187267413. The reversal of 28187267400 is 476278182.

28187267400 is a `hidden beast` number, since 2 + 8 + 187 + 2 + 67 + 400 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 367028964 + 27820238436 = 19158^2 + 166794^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1163410 + ... + 1187390.

Almost surely, 2^28187267400 is an apocalyptic number.

28187267400 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 28187267400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47405579130).

28187267400 is an abundant number, since it is smaller than the sum of its proper divisors (66623890860).

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

28187267400 is a wasteful number, since it uses less digits than its factorization.

28187267400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24656 (or 24644 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 45.

The spelling of 28187267400 in words is "twenty-eight billion, one hundred eighty-seven million, two hundred sixty-seven thousand, four hundred".