215135257 has 8 divisors (see below), whose sum is σ = 222243840. Its totient is φ = 208037280.

The previous prime is 215135251. The next prime is 215135269. The reversal of 215135257 is 752531512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 215135257 - 2¹⁹ = 214610969 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215135251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 77469 + ... + 80197.

It is an arithmetic number, because the mean of its divisors is an integer number (27780480).

Almost surely, 2^215135257 is an apocalyptic number.

It is an amenable number.

215135257 is a deficient number, since it is larger than the sum of its proper divisors (7108583).

215135257 is a wasteful number, since it uses less digits than its factorization.

215135257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5303.

The product of its digits is 10500, while the sum is 31.

The square root of 215135257 is about 14667.4897988715. The cubic root of 215135257 is about 599.1982411522.

Adding to 215135257 its reverse (752531512), we get a palindrome (967666769).

The spelling of 215135257 in words is "two hundred fifteen million, one hundred thirty-five thousand, two hundred fifty-seven".