11521399999 has 8 divisors (see below), whose sum is σ = 11582464608. Its totient is φ = 11460445440.

The previous prime is 11521399957. The next prime is 11521400003. The reversal of 11521399999 is 99999312511.

It is a happy number.

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 11521399999 - 2⁷ = 11521399871 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 (11521399909) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 186819 + ... + 240715.

It is an arithmetic number, because the mean of its divisors is an integer number (1447808076).

Almost surely, 2^11521399999 is an apocalyptic number.

11521399999 is a deficient number, since it is larger than the sum of its proper divisors (61064609).

11521399999 is an equidigital number, since it uses as much as digits as its factorization.

11521399999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55025.

The product of its digits is 1771470, while the sum is 58.

The spelling of 11521399999 in words is "eleven billion, five hundred twenty-one million, three hundred ninety-nine thousand, nine hundred ninety-nine".