6551288021 has 2 divisors, whose sum is σ = 6551288022. Its totient is φ = 6551288020.

The previous prime is 6551288017. The next prime is 6551288047. The reversal of 6551288021 is 1208821556.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5489179921 + 1062108100 = 74089^2 + 32590^2 .

It is a cyclic number.

It is not a de Polignac number, because 6551288021 - 2² = 6551288017 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6551288071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3275644010 + 3275644011.

It is an arithmetic number, because the mean of its divisors is an integer number (3275644011).

Almost surely, 2^6551288021 is an apocalyptic number.

It is an amenable number.

6551288021 is a deficient number, since it is larger than the sum of its proper divisors (1).

6551288021 is an equidigital number, since it uses as much as digits as its factorization.

6551288021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 38400, while the sum is 38.

The square root of 6551288021 is about 80940.0273103487. The cubic root of 6551288021 is about 1871.1512657790.

The spelling of 6551288021 in words is "six billion, five hundred fifty-one million, two hundred eighty-eight thousand, twenty-one".