1864387728 has 480 divisors, whose sum is σ = 6685286400. Its totient is φ = 473324544.

The previous prime is 1864387727. The next prime is 1864387747. The reversal of 1864387728 is 8277834681.

It is a happy number.

1864387728 is a `hidden beast` number, since 186 + 438 + 7 + 7 + 28 = 666.

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (1864387727) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 31599763 + ... + 31599821.

It is an arithmetic number, because the mean of its divisors is an integer number (13927680).

Almost surely, 2^1864387728 is an apocalyptic number.

1864387728 is a gapful number since it is divisible by the number (18) 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 1864387728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3342643200).

1864387728 is an abundant number, since it is smaller than the sum of its proper divisors (4820898672).

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

1864387728 is a wasteful number, since it uses less digits than its factorization.

1864387728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179 (or 170 counting only the distinct ones).

The product of its digits is 3612672, while the sum is 54.

The square root of 1864387728 is about 43178.5563445560. The cubic root of 1864387728 is about 1230.7752241711.

The spelling of 1864387728 in words is "one billion, eight hundred sixty-four million, three hundred eighty-seven thousand, seven hundred twenty-eight".