2005221551 has 2 divisors, whose sum is σ = 2005221552. Its totient is φ = 2005221550.

The previous prime is 2005221541. The next prime is 2005221607. The reversal of 2005221551 is 1551225002.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2005221551 - 2¹⁰ = 2005220527 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2005221511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1002610775 + 1002610776.

It is an arithmetic number, because the mean of its divisors is an integer number (1002610776).

Almost surely, 2^2005221551 is an apocalyptic number.

2005221551 is a deficient number, since it is larger than the sum of its proper divisors (1).

2005221551 is an equidigital number, since it uses as much as digits as its factorization.

2005221551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 2005221551 is about 44779.7002111448. The cubic root of 2005221551 is about 1261.0165540784.

Adding to 2005221551 its reverse (1551225002), we get a palindrome (3556446553).

The spelling of 2005221551 in words is "two billion, five million, two hundred twenty-one thousand, five hundred fifty-one".