215054251 has 4 divisors (see below), whose sum is σ = 215265904. Its totient is φ = 214842600.

The previous prime is 215054239. The next prime is 215054299. The reversal of 215054251 is 152450512.

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 215054251 - 2¹³ = 215046059 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215054201) 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, 104295 + ... + 106336.

It is an arithmetic number, because the mean of its divisors is an integer number (53816476).

Almost surely, 2^215054251 is an apocalyptic number.

215054251 is a deficient number, since it is larger than the sum of its proper divisors (211653).

215054251 is a wasteful number, since it uses less digits than its factorization.

215054251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211652.

The product of its (nonzero) digits is 2000, while the sum is 25.

The square root of 215054251 is about 14664.7281256762. The cubic root of 215054251 is about 599.1230252983.

The spelling of 215054251 in words is "two hundred fifteen million, fifty-four thousand, two hundred fifty-one".