1387806720 has 120 divisors (see below), whose sum is σ = 4441632384. Its totient is φ = 370016256.

The previous prime is 1387806709. The next prime is 1387806727. The reversal of 1387806720 is 276087831.

It is a tau number, because it is divible by the number of its divisors (120).

It is not an unprimeable number, because it can be changed into a prime (1387806727) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 242937 + ... + 248583.

Almost surely, 2^1387806720 is an apocalyptic number.

1387806720 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 1387806720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2220816192).

1387806720 is an abundant number, since it is smaller than the sum of its proper divisors (3053825664).

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

1387806720 is an frugal number, since it uses more digits than its factorization.

1387806720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5683 (or 5657 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 42.

The square root of 1387806720 is about 37253.2779765754. The cubic root of 1387806720 is about 1115.4317323723.

The spelling of 1387806720 in words is "one billion, three hundred eighty-seven million, eight hundred six thousand, seven hundred twenty".