215512551 has 12 divisors (see below), whose sum is σ = 311426128. Its totient is φ = 143614944.

The previous prime is 215512513. The next prime is 215512559. The reversal of 215512551 is 155215512.

It is not a de Polignac number, because 215512551 - 2⁹ = 215512039 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215512559) 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 11 ways as a sum of consecutive naturals, for example, 32451 + ... + 38523.

Almost surely, 2^215512551 is an apocalyptic number.

215512551 is a deficient number, since it is larger than the sum of its proper divisors (95913577).

215512551 is a wasteful number, since it uses less digits than its factorization.

215512551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10022 (or 10019 counting only the distinct ones).

The product of its digits is 2500, while the sum is 27.

The square root of 215512551 is about 14680.3457384355. The cubic root of 215512551 is about 599.5483183915.

It can be divided in two parts, 2155 and 12551, that added together give a triangular number (14706 = T₁₇₁).

The spelling of 215512551 in words is "two hundred fifteen million, five hundred twelve thousand, five hundred fifty-one".