121405156 has 12 divisors (see below), whose sum is σ = 212991660. Its totient is φ = 60550400.

The previous prime is 121405147. The next prime is 121405169. The reversal of 121405156 is 651504121.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 120648256 + 756900 = 10984^2 + 870^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 121405156.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36241 + ... + 39448.

It is an arithmetic number, because the mean of its divisors is an integer number (17749305).

Almost surely, 2^121405156 is an apocalyptic number.

It is an amenable number.

121405156 is a deficient number, since it is larger than the sum of its proper divisors (91586504).

121405156 is a wasteful number, since it uses less digits than its factorization.

121405156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76094 (or 76092 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 121405156 is about 11018.4007914034. The cubic root of 121405156 is about 495.1601780706.

Adding to 121405156 its reverse (651504121), we get a palindrome (772909277).

The spelling of 121405156 in words is "one hundred twenty-one million, four hundred five thousand, one hundred fifty-six".