1388897520 has 80 divisors (see below), whose sum is σ = 4325056512. Its totient is φ = 368697600.

The previous prime is 1388897513. The next prime is 1388897533. The reversal of 1388897520 is 257988831.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-3 number, since 3×1388897520³ (a number of 28 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40545 + ... + 66495.

Almost surely, 2^1388897520 is an apocalyptic number.

1388897520 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 1388897520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2162528256).

1388897520 is an abundant number, since it is smaller than the sum of its proper divisors (2936158992).

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

1388897520 is a wasteful number, since it uses less digits than its factorization.

1388897520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26190 (or 26184 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 51.

The square root of 1388897520 is about 37267.9154233236. The cubic root of 1388897520 is about 1115.7238946456.

The spelling of 1388897520 in words is "one billion, three hundred eighty-eight million, eight hundred ninety-seven thousand, five hundred twenty".