1551516409 has 2 divisors, whose sum is σ = 1551516410. Its totient is φ = 1551516408.

The previous prime is 1551516391. The next prime is 1551516413. The reversal of 1551516409 is 9046151551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1443772009 + 107744400 = 37997^2 + 10380^2 .

It is a cyclic number.

It is not a de Polignac number, because 1551516409 - 2¹¹ = 1551514361 is a prime.

It is not a weakly prime, because it can be changed into another prime (1551516209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 775758204 + 775758205.

It is an arithmetic number, because the mean of its divisors is an integer number (775758205).

Almost surely, 2^1551516409 is an apocalyptic number.

It is an amenable number.

1551516409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1551516409 is an equidigital number, since it uses as much as digits as its factorization.

1551516409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27000, while the sum is 37.

The square root of 1551516409 is about 39389.2930756570. The cubic root of 1551516409 is about 1157.6718089506.

The spelling of 1551516409 in words is "one billion, five hundred fifty-one million, five hundred sixteen thousand, four hundred nine".