1236421 has 4 divisors (see below), whose sum is σ = 1239052. Its totient is φ = 1233792.

The previous prime is 1236419. The next prime is 1236439. The reversal of 1236421 is 1246321.

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

It can be written as a sum of positive squares in 2 ways, for example, as 408321 + 828100 = 639^2 + 910^2 .

It is a cyclic number.

It is not a de Polignac number, because 1236421 - 2¹ = 1236419 is a prime.

It is a Duffinian number.

1236421 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1236481) 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, 396 + ... + 1621.

It is an arithmetic number, because the mean of its divisors is an integer number (309763).

2^1236421 is an apocalyptic number.

It is an amenable number.

1236421 is a deficient number, since it is larger than the sum of its proper divisors (2631).

1236421 is an equidigital number, since it uses as much as digits as its factorization.

1236421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2630.

The product of its digits is 288, while the sum is 19.

The square root of 1236421 is about 1111.9446928692. The cubic root of 1236421 is about 107.3302458722.

The spelling of 1236421 in words is "one million, two hundred thirty-six thousand, four hundred twenty-one".