1387477728 has 288 divisors, whose sum is σ = 5071641120. Its totient is φ = 365783040.

The previous prime is 1387477727. The next prime is 1387477753. The reversal of 1387477728 is 8277747831.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (54).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1387477727) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 549108 + ... + 551628.

It is an arithmetic number, because the mean of its divisors is an integer number (17609865).

Almost surely, 2^1387477728 is an apocalyptic number.

1387477728 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 1387477728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2535820560).

1387477728 is an abundant number, since it is smaller than the sum of its proper divisors (3684163392).

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

1387477728 is a wasteful number, since it uses less digits than its factorization.

1387477728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2567 (or 2546 counting only the distinct ones).

The product of its digits is 3687936, while the sum is 54.

The square root of 1387477728 is about 37248.8621034254. The cubic root of 1387477728 is about 1115.3435843824.

The spelling of 1387477728 in words is "one billion, three hundred eighty-seven million, four hundred seventy-seven thousand, seven hundred twenty-eight".