11211521616 has 30 divisors (see below), whose sum is σ = 31376689370. Its totient is φ = 3737173824.

The previous prime is 11211521599. The next prime is 11211521687. The reversal of 11211521616 is 61612511211.

11211521616 is a `hidden beast` number, since 1 + 1 + 21 + 1 + 5 + 21 + 616 = 666.

It can be written as a sum of positive squares in only one way, i.e., 9611841600 + 1599680016 = 98040^2 + 39996^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 11211521616.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38928751 + ... + 38929038.

Almost surely, 2^11211521616 is an apocalyptic number.

11211521616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

11211521616 is an abundant number, since it is smaller than the sum of its proper divisors (20165167754).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11211521616 is a wasteful number, since it uses less digits than its factorization.

11211521616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77857803 (or 77857794 counting only the distinct ones).

The product of its digits is 720, while the sum is 27.

The spelling of 11211521616 in words is "eleven billion, two hundred eleven million, five hundred twenty-one thousand, six hundred sixteen".