11999551 has 2 divisors, whose sum is σ = 11999552. Its totient is φ = 11999550.

The previous prime is 11999531. The next prime is 11999563. The reversal of 11999551 is 15599911.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11999551 - 2⁷ = 11999423 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11999531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5999775 + 5999776.

It is an arithmetic number, because the mean of its divisors is an integer number (5999776).

Almost surely, 2^11999551 is an apocalyptic number.

11999551 is a deficient number, since it is larger than the sum of its proper divisors (1).

11999551 is an equidigital number, since it uses as much as digits as its factorization.

11999551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18225, while the sum is 40.

The square root of 11999551 is about 3464.0368069638. The cubic root of 11999551 is about 228.9399930490.

The spelling of 11999551 in words is "eleven million, nine hundred ninety-nine thousand, five hundred fifty-one".