1315515251 has 4 divisors (see below), whose sum is σ = 1316561400. Its totient is φ = 1314469104.

The previous prime is 1315515239. The next prime is 1315515259. The reversal of 1315515251 is 1525155131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1525155131 = 28439 ⋅53629.

It is a cyclic number.

It is not a de Polignac number, because 1315515251 - 2²⁶ = 1248406387 is a prime.

It is a super-2 number, since 2×1315515251² = 3461160751227186002, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1315515259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 521186 + ... + 523703.

It is an arithmetic number, because the mean of its divisors is an integer number (329140350).

Almost surely, 2^1315515251 is an apocalyptic number.

1315515251 is a deficient number, since it is larger than the sum of its proper divisors (1046149).

1315515251 is a wasteful number, since it uses less digits than its factorization.

1315515251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1046148.

The product of its digits is 3750, while the sum is 29.

The square root of 1315515251 is about 36270.0324096905. The cubic root of 1315515251 is about 1095.7175786219.

The spelling of 1315515251 in words is "one billion, three hundred fifteen million, five hundred fifteen thousand, two hundred fifty-one".