121440405 has 16 divisors (see below), whose sum is σ = 194482944. Its totient is φ = 64708800.

The previous prime is 121440377. The next prime is 121440409. The reversal of 121440405 is 504044121.

It is a happy number.

It is not a de Polignac number, because 121440405 - 2¹² = 121436309 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121440409) 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 15 ways as a sum of consecutive naturals, for example, 16855 + ... + 22955.

It is an arithmetic number, because the mean of its divisors is an integer number (12155184).

Almost surely, 2^121440405 is an apocalyptic number.

121440405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121440405 is a deficient number, since it is larger than the sum of its proper divisors (73042539).

121440405 is a wasteful number, since it uses less digits than its factorization.

121440405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7436.

The product of its (nonzero) digits is 640, while the sum is 21.

The square root of 121440405 is about 11020.0002268603. Note that the first 3 decimals coincide. The cubic root of 121440405 is about 495.2080953441.

Adding to 121440405 its reverse (504044121), we get a palindrome (625484526).

The spelling of 121440405 in words is "one hundred twenty-one million, four hundred forty thousand, four hundred five".