1388421 has 20 divisors (see below), whose sum is σ = 2115564. Its totient is φ = 907200.

The previous prime is 1388419. The next prime is 1388449. The reversal of 1388421 is 1248831.

It can be written as a sum of positive squares in 2 ways, for example, as 408321 + 980100 = 639^2 + 990^2 .

It is not a de Polignac number, because 1388421 - 2¹ = 1388419 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1388411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4801 + ... + 5081.

2^1388421 is an apocalyptic number.

It is an amenable number.

1388421 is a deficient number, since it is larger than the sum of its proper divisors (727143).

1388421 is an equidigital number, since it uses as much as digits as its factorization.

1388421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354 (or 345 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 1388421 is about 1178.3127768127. The cubic root of 1388421 is about 111.5596281303.

The spelling of 1388421 in words is "one million, three hundred eighty-eight thousand, four hundred twenty-one".