1242689 has 8 divisors (see below), whose sum is σ = 1449600. Its totient is φ = 1064868.

The previous prime is 1242643. The next prime is 1242739. The reversal of 1242689 is 9862421.

It is not a de Polignac number, because 1242689 - 2¹⁶ = 1177153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1242629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1469 + ... + 2154.

It is an arithmetic number, because the mean of its divisors is an integer number (181200).

2^1242689 is an apocalyptic number.

It is an amenable number.

1242689 is a deficient number, since it is larger than the sum of its proper divisors (206911).

1242689 is an frugal number, since it uses more digits than its factorization.

1242689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3644 (or 3630 counting only the distinct ones).

The product of its digits is 6912, while the sum is 32.

The square root of 1242689 is about 1114.7596153431. The cubic root of 1242689 is about 107.5113094285.

The spelling of 1242689 in words is "one million, two hundred forty-two thousand, six hundred eighty-nine".