551242121 has 4 divisors (see below), whose sum is σ = 570250500. Its totient is φ = 532233744.

The previous prime is 551242099. The next prime is 551242129. The reversal of 551242121 is 121242155.

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

It can be written as a sum of positive squares in 2 ways, for example, as 447914896 + 103327225 = 21164^2 + 10165^2 .

It is a cyclic number.

It is not a de Polignac number, because 551242121 - 2¹⁴ = 551225737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (551242129) 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, 9504146 + ... + 9504203.

It is an arithmetic number, because the mean of its divisors is an integer number (142562625).

Almost surely, 2^551242121 is an apocalyptic number.

It is an amenable number.

551242121 is a deficient number, since it is larger than the sum of its proper divisors (19008379).

551242121 is a wasteful number, since it uses less digits than its factorization.

551242121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19008378.

The product of its digits is 800, while the sum is 23.

The square root of 551242121 is about 23478.5459728664. The cubic root of 551242121 is about 819.9375924149.

Adding to 551242121 its reverse (121242155), we get a palindrome (672484276).

The spelling of 551242121 in words is "five hundred fifty-one million, two hundred forty-two thousand, one hundred twenty-one".