551001021 has 16 divisors (see below), whose sum is σ = 740833536. Its totient is φ = 364262976.

The previous prime is 551000987. The next prime is 551001049. The reversal of 551001021 is 120100155.

It is not a de Polignac number, because 551001021 - 2⁹ = 551000509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (551001721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 239151 + ... + 241443.

It is an arithmetic number, because the mean of its divisors is an integer number (46302096).

Almost surely, 2^551001021 is an apocalyptic number.

It is an amenable number.

551001021 is a deficient number, since it is larger than the sum of its proper divisors (189832515).

551001021 is a wasteful number, since it uses less digits than its factorization.

551001021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2932.

The product of its (nonzero) digits is 50, while the sum is 15.

The square root of 551001021 is about 23473.4109366321. The cubic root of 551001021 is about 819.8180346778.

Adding to 551001021 its reverse (120100155), we get a palindrome (671101176).

The spelling of 551001021 in words is "five hundred fifty-one million, one thousand, twenty-one".