1388628540 has 144 divisors (see below), whose sum is σ = 4553316768. Its totient is φ = 340526592.

The previous prime is 1388628529. The next prime is 1388628607. The reversal of 1388628540 is 458268831.

1388628540 is a `hidden beast` number, since 1 + 3 + 8 + 86 + 28 + 540 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 717414 + ... + 719346.

Almost surely, 2^1388628540 is an apocalyptic number.

1388628540 is a gapful number since it is divisible by the number (10) 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 1388628540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2276658384).

1388628540 is an abundant number, since it is smaller than the sum of its proper divisors (3164688228).

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

1388628540 is a wasteful number, since it uses less digits than its factorization.

1388628540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2268 (or 2263 counting only the distinct ones).

The product of its (nonzero) digits is 368640, while the sum is 45.

The square root of 1388628540 is about 37264.3065144113. The cubic root of 1388628540 is about 1115.6518646639.

The spelling of 1388628540 in words is "one billion, three hundred eighty-eight million, six hundred twenty-eight thousand, five hundred forty".