121440401 has 24 divisors (see below), whose sum is σ = 136212216. Its totient is φ = 108103680.

The previous prime is 121440377. The next prime is 121440409. The reversal of 121440401 is 104044121.

It is a Cunningham number, because it is equal to 11020²+1.

It can be written as a sum of positive squares in 12 ways, for example, as 12780625 + 108659776 = 3575^2 + 10424^2 .

It is a de Polignac number, because none of the positive numbers 2^k-121440401 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121440401.

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 polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 438275 + ... + 438551.

It is an arithmetic number, because the mean of its divisors is an integer number (5675509).

Almost surely, 2^121440401 is an apocalyptic number.

It is an amenable number.

121440401 is a deficient number, since it is larger than the sum of its proper divisors (14771815).

121440401 is a wasteful number, since it uses less digits than its factorization.

121440401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389 (or 372 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 121440401 is about 11020.0000453721. Note that the first 4 decimals coincide. The cubic root of 121440401 is about 495.2080899070.

Adding to 121440401 its reverse (104044121), we get a palindrome (225484522).

The spelling of 121440401 in words is "one hundred twenty-one million, four hundred forty thousand, four hundred one".