121211616 has 24 divisors (see below), whose sum is σ = 318180744. Its totient is φ = 40403840.

The previous prime is 121211603. The next prime is 121211617. The reversal of 121211616 is 616112121.

It is a tau number, because it is divible by the number of its divisors (24).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 121211592 and 121211601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121211617) 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 3 ways as a sum of consecutive naturals, for example, 631215 + ... + 631406.

It is an arithmetic number, because the mean of its divisors is an integer number (13257531).

Almost surely, 2^121211616 is an apocalyptic number.

121211616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

121211616 is an abundant number, since it is smaller than the sum of its proper divisors (196969128).

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

121211616 is a wasteful number, since it uses less digits than its factorization.

121211616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1262634 (or 1262626 counting only the distinct ones).

The product of its digits is 144, while the sum is 21.

The square root of 121211616 is about 11009.6147071548. The cubic root of 121211616 is about 494.8969155813.

Adding to 121211616 its reverse (616112121), we get a palindrome (737323737).

The spelling of 121211616 in words is "one hundred twenty-one million, two hundred eleven thousand, six hundred sixteen".