1315657728 has 480 divisors, whose sum is σ = 4947022080. Its totient is φ = 338411520.

The previous prime is 1315657711. The next prime is 1315657741. The reversal of 1315657728 is 8277565131.

It is a happy number.

1315657728 is a `hidden beast` number, since 1 + 3 + 1 + 56 + 577 + 28 = 666.

It is a super-2 number, since 2×1315657728² = 3461910514492243968, which contains 22 as substring.

Its product of digits (352800) is a multiple of the sum of its prime divisors (126).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 12773325 + ... + 12773427.

It is an arithmetic number, because the mean of its divisors is an integer number (10306296).

Almost surely, 2^1315657728 is an apocalyptic number.

1315657728 is a gapful number since it is divisible by the number (18) 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 1315657728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2473511040).

1315657728 is an abundant number, since it is smaller than the sum of its proper divisors (3631364352).

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

1315657728 is a wasteful number, since it uses less digits than its factorization.

1315657728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155 (or 126 counting only the distinct ones).

The product of its digits is 352800, while the sum is 45.

The square root of 1315657728 is about 36271.9964711070. The cubic root of 1315657728 is about 1095.7571344582.

The spelling of 1315657728 in words is "one billion, three hundred fifteen million, six hundred fifty-seven thousand, seven hundred twenty-eight".