1385537440 has 96 divisors (see below), whose sum is σ = 3820690944. Its totient is φ = 464916480.

The previous prime is 1385537431. The next prime is 1385537449. The reversal of 1385537440 is 447355831.

It is an interprime number because it is at equal distance from previous prime (1385537431) and next prime (1385537449).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 1385537393 and 1385537402.

It is not an unprimeable number, because it can be changed into a prime (1385537449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39480 + ... + 65800.

It is an arithmetic number, because the mean of its divisors is an integer number (39798864).

Almost surely, 2^1385537440 is an apocalyptic number.

1385537440 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 1385537440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1910345472).

1385537440 is an abundant number, since it is smaller than the sum of its proper divisors (2435153504).

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

1385537440 is a wasteful number, since it uses less digits than its factorization.

1385537440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26390 (or 26382 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 40.

The square root of 1385537440 is about 37222.8080617247. The cubic root of 1385537440 is about 1114.8234325301.

The spelling of 1385537440 in words is "one billion, three hundred eighty-five million, five hundred thirty-seven thousand, four hundred forty".