121511616 has 56 divisors (see below), whose sum is σ = 327592944. Its totient is φ = 39736320.

The previous prime is 121511587. The next prime is 121511617. The reversal of 121511616 is 616115121.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121511617) 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, 4206 + ... + 16146.

It is an arithmetic number, because the mean of its divisors is an integer number (5849874).

Almost surely, 2^121511616 is an apocalyptic number.

121511616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121511616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163796472).

121511616 is an abundant number, since it is smaller than the sum of its proper divisors (206081328).

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

121511616 is a wasteful number, since it uses less digits than its factorization.

121511616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12009 (or 11999 counting only the distinct ones).

The product of its digits is 360, while the sum is 24.

The square root of 121511616 is about 11023.2307423913. The cubic root of 121511616 is about 495.3048708588.

Adding to 121511616 its reverse (616115121), we get a palindrome (737626737).

The spelling of 121511616 in words is "one hundred twenty-one million, five hundred eleven thousand, six hundred sixteen".