1557878340 has 96 divisors (see below), whose sum is σ = 4624671744. Its totient is φ = 391150080.

The previous prime is 1557878323. The next prime is 1557878359. The reversal of 1557878340 is 438787551.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1557878340.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 57502 + ... + 80138.

It is an arithmetic number, because the mean of its divisors is an integer number (48173664).

Almost surely, 2^1557878340 is an apocalyptic number.

1557878340 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 1557878340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2312335872).

1557878340 is an abundant number, since it is smaller than the sum of its proper divisors (3066793404).

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

1557878340 is a wasteful number, since it uses less digits than its factorization.

1557878340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22717 (or 22715 counting only the distinct ones).

The product of its (nonzero) digits is 940800, while the sum is 48.

The square root of 1557878340 is about 39469.9675702932. The cubic root of 1557878340 is about 1159.2519800934.

The spelling of 1557878340 in words is "one billion, five hundred fifty-seven million, eight hundred seventy-eight thousand, three hundred forty".