6487151221 has 2 divisors, whose sum is σ = 6487151222. Its totient is φ = 6487151220.

The previous prime is 6487151191. The next prime is 6487151249. The reversal of 6487151221 is 1221517846.

6487151221 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5236114321 + 1251036900 = 72361^2 + 35370^2 .

It is a cyclic number.

It is not a de Polignac number, because 6487151221 - 2⁵ = 6487151189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6487151291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3243575610 + 3243575611.

It is an arithmetic number, because the mean of its divisors is an integer number (3243575611).

Almost surely, 2^6487151221 is an apocalyptic number.

It is an amenable number.

6487151221 is a deficient number, since it is larger than the sum of its proper divisors (1).

6487151221 is an equidigital number, since it uses as much as digits as its factorization.

6487151221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 26880, while the sum is 37.

The square root of 6487151221 is about 80542.8533204530. The cubic root of 6487151221 is about 1865.0250695382.

The spelling of 6487151221 in words is "six billion, four hundred eighty-seven million, one hundred fifty-one thousand, two hundred twenty-one".