551221207 has 4 divisors (see below), whose sum is σ = 551277160. Its totient is φ = 551165256.

The previous prime is 551221117. The next prime is 551221211. The reversal of 551221207 is 702122155.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 551221207 - 2²⁷ = 417003479 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 (551221807) 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, 8832 + ... + 34357.

It is an arithmetic number, because the mean of its divisors is an integer number (137819290).

Almost surely, 2^551221207 is an apocalyptic number.

551221207 is a deficient number, since it is larger than the sum of its proper divisors (55953).

551221207 is a wasteful number, since it uses less digits than its factorization.

551221207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55952.

The product of its (nonzero) digits is 1400, while the sum is 25.

The square root of 551221207 is about 23478.1005833095. The cubic root of 551221207 is about 819.9272228688.

The spelling of 551221207 in words is "five hundred fifty-one million, two hundred twenty-one thousand, two hundred seven".