1236145 has 4 divisors (see below), whose sum is σ = 1483380. Its totient is φ = 988912.

The previous prime is 1236077. The next prime is 1236161. The reversal of 1236145 is 5416321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5416321 = 659 ⋅8219.

It can be written as a sum of positive squares in 2 ways, for example, as 238144 + 998001 = 488^2 + 999^2 .

It is a cyclic number.

It is not a de Polignac number, because 1236145 - 2⁷ = 1236017 is a prime.

It is a super-2 number, since 2×1236145² = 3056108922050, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 123610 + ... + 123619.

It is an arithmetic number, because the mean of its divisors is an integer number (370845).

2^1236145 is an apocalyptic number.

It is an amenable number.

1236145 is a deficient number, since it is larger than the sum of its proper divisors (247235).

1236145 is an equidigital number, since it uses as much as digits as its factorization.

1236145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247234.

The product of its digits is 720, while the sum is 22.

The square root of 1236145 is about 1111.8205790504. The cubic root of 1236145 is about 107.3222590154.

It can be divided in two parts, 123 and 6145, that multiplied together give a triangular number (755835 = T₁₂₂₉).

The spelling of 1236145 in words is "one million, two hundred thirty-six thousand, one hundred forty-five".