215212051 has 4 divisors (see below), whose sum is σ = 215346600. Its totient is φ = 215077504.

The previous prime is 215212043. The next prime is 215212073. The reversal of 215212051 is 150212512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 215212051 - 2³ = 215212043 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215212001) 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 3 ways as a sum of consecutive naturals, for example, 64846 + ... + 68083.

It is an arithmetic number, because the mean of its divisors is an integer number (53836650).

Almost surely, 2^215212051 is an apocalyptic number.

215212051 is a deficient number, since it is larger than the sum of its proper divisors (134549).

215212051 is a wasteful number, since it uses less digits than its factorization.

215212051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134548.

The product of its (nonzero) digits is 200, while the sum is 19.

The square root of 215212051 is about 14670.1073956532. The cubic root of 215212051 is about 599.2695286395.

Adding to 215212051 its reverse (150212512), we get a palindrome (365424563).

The spelling of 215212051 in words is "two hundred fifteen million, two hundred twelve thousand, fifty-one".