121940399 has 4 divisors (see below), whose sum is σ = 139360464. Its totient is φ = 104520336.

The previous prime is 121940387. The next prime is 121940407. The reversal of 121940399 is 993049121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 121940399 - 2⁴ = 121940383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121940339) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8710022 + ... + 8710035.

It is an arithmetic number, because the mean of its divisors is an integer number (34840116).

Almost surely, 2^121940399 is an apocalyptic number.

121940399 is a deficient number, since it is larger than the sum of its proper divisors (17420065).

121940399 is an equidigital number, since it uses as much as digits as its factorization.

121940399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17420064.

The product of its (nonzero) digits is 17496, while the sum is 38.

The square root of 121940399 is about 11042.6626770902. The cubic root of 121940399 is about 495.8867877560.

The spelling of 121940399 in words is "one hundred twenty-one million, nine hundred forty thousand, three hundred ninety-nine".