2551400221 has 2 divisors, whose sum is σ = 2551400222. Its totient is φ = 2551400220.

The previous prime is 2551400197. The next prime is 2551400261. The reversal of 2551400221 is 1220041552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2103231321 + 448168900 = 45861^2 + 21170^2 .

It is a cyclic number.

It is not a de Polignac number, because 2551400221 - 2¹⁹ = 2550875933 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2551400192 and 2551400201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2551400261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1275700110 + 1275700111.

It is an arithmetic number, because the mean of its divisors is an integer number (1275700111).

Almost surely, 2^2551400221 is an apocalyptic number.

It is an amenable number.

2551400221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2551400221 is an equidigital number, since it uses as much as digits as its factorization.

2551400221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 2551400221 is about 50511.3870429233. The cubic root of 2551400221 is about 1366.4472247773.

Adding to 2551400221 its reverse (1220041552), we get a palindrome (3771441773).

The spelling of 2551400221 in words is "two billion, five hundred fifty-one million, four hundred thousand, two hundred twenty-one".