1378121 has 4 divisors (see below), whose sum is σ = 1386000. Its totient is φ = 1370244.

The previous prime is 1378103. The next prime is 1378129. The reversal of 1378121 is 1218731.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1378121 - 2⁶ = 1378057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1378129) 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, 3671 + ... + 4028.

It is an arithmetic number, because the mean of its divisors is an integer number (346500).

2^1378121 is an apocalyptic number.

It is an amenable number.

1378121 is a deficient number, since it is larger than the sum of its proper divisors (7879).

1378121 is an equidigital number, since it uses as much as digits as its factorization.

1378121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7878.

The product of its digits is 336, while the sum is 23.

The square root of 1378121 is about 1173.9339845153. The cubic root of 1378121 is about 111.2830747932.

The spelling of 1378121 in words is "one million, three hundred seventy-eight thousand, one hundred twenty-one".