5128278521 has 2 divisors, whose sum is σ = 5128278522. Its totient is φ = 5128278520.

The previous prime is 5128278517. The next prime is 5128278553. The reversal of 5128278521 is 1258728215.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2654310400 + 2473968121 = 51520^2 + 49739^2 .

It is a cyclic number.

It is not a de Polignac number, because 5128278521 - 2² = 5128278517 is a prime.

It is not a weakly prime, because it can be changed into another prime (5128278721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2564139260 + 2564139261.

It is an arithmetic number, because the mean of its divisors is an integer number (2564139261).

Almost surely, 2^5128278521 is an apocalyptic number.

It is an amenable number.

5128278521 is a deficient number, since it is larger than the sum of its proper divisors (1).

5128278521 is an equidigital number, since it uses as much as digits as its factorization.

5128278521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 89600, while the sum is 41.

The square root of 5128278521 is about 71611.9998394124. Note that the first 3 decimals coincide. The cubic root of 5128278521 is about 1724.4761858120.

The spelling of 5128278521 in words is "five billion, one hundred twenty-eight million, two hundred seventy-eight thousand, five hundred twenty-one".