201222551 has 4 divisors (see below), whose sum is σ = 203176272. Its totient is φ = 199268832.

The previous prime is 201222533. The next prime is 201222577. The reversal of 201222551 is 155222102.

It is a happy number.

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 201222551 - 2⁶ = 201222487 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 (201222451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 976706 + ... + 976911.

It is an arithmetic number, because the mean of its divisors is an integer number (50794068).

Almost surely, 2^201222551 is an apocalyptic number.

201222551 is a deficient number, since it is larger than the sum of its proper divisors (1953721).

201222551 is a wasteful number, since it uses less digits than its factorization.

201222551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1953720.

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 201222551 is about 14185.2934759913. The cubic root of 201222551 is about 585.9927148314.

Adding to 201222551 its reverse (155222102), we get a palindrome (356444653).

The spelling of 201222551 in words is "two hundred one million, two hundred twenty-two thousand, five hundred fifty-one".