12011551 has 8 divisors (see below), whose sum is σ = 12200864. Its totient is φ = 11823840.

The previous prime is 12011513. The next prime is 12011557. The reversal of 12011551 is 15511021.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12011551 - 2¹³ = 12003359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12011557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28321 + ... + 28741.

It is an arithmetic number, because the mean of its divisors is an integer number (1525108).

Almost surely, 2^12011551 is an apocalyptic number.

12011551 is a deficient number, since it is larger than the sum of its proper divisors (189313).

12011551 is a wasteful number, since it uses less digits than its factorization.

12011551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801.

The product of its (nonzero) digits is 50, while the sum is 16.

The square root of 12011551 is about 3465.7684573555. The cubic root of 12011551 is about 229.0162838099.

Adding to 12011551 its reverse (15511021), we get a palindrome (27522572).

The spelling of 12011551 in words is "twelve million, eleven thousand, five hundred fifty-one".