551080661 has 4 divisors (see below), whose sum is σ = 551140800. Its totient is φ = 551020524.

The previous prime is 551080639. The next prime is 551080679. The reversal of 551080661 is 166080155.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 166080155 = 5 ⋅33216031.

It is a cyclic number.

It is not a de Polignac number, because 551080661 - 2⁶ = 551080597 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 (551080681) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13151 + ... + 35708.

It is an arithmetic number, because the mean of its divisors is an integer number (137785200).

Almost surely, 2^551080661 is an apocalyptic number.

It is an amenable number.

551080661 is a deficient number, since it is larger than the sum of its proper divisors (60139).

551080661 is a wasteful number, since it uses less digits than its factorization.

551080661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60138.

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 551080661 is about 23475.1072628007. The cubic root of 551080661 is about 819.8575307709.

The spelling of 551080661 in words is "five hundred fifty-one million, eighty thousand, six hundred sixty-one".