11551285491 has 4 divisors (see below), whose sum is σ = 15401713992. Its totient is φ = 7700856992.

The previous prime is 11551285433. The next prime is 11551285507. The reversal of 11551285491 is 19458215511.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 11551285491 - 2¹⁰ = 11551284467 is a prime.

It is a super-2 number, since 2×11551285491² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (11551285891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1925214246 + ... + 1925214251.

It is an arithmetic number, because the mean of its divisors is an integer number (3850428498).

Almost surely, 2^11551285491 is an apocalyptic number.

11551285491 is a deficient number, since it is larger than the sum of its proper divisors (3850428501).

11551285491 is an equidigital number, since it uses as much as digits as its factorization.

11551285491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3850428500.

The product of its digits is 72000, while the sum is 42.

The spelling of 11551285491 in words is "eleven billion, five hundred fifty-one million, two hundred eighty-five thousand, four hundred ninety-one".