1866407 has 4 divisors (see below), whose sum is σ = 1883640. Its totient is φ = 1849176.

The previous prime is 1866373. The next prime is 1866409. The reversal of 1866407 is 7046681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7046681 = 29 ⋅242989.

It is a cyclic number.

It is not a de Polignac number, because 1866407 - 2⁶ = 1866343 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1866409) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8453 + ... + 8670.

It is an arithmetic number, because the mean of its divisors is an integer number (470910).

2^1866407 is an apocalyptic number.

1866407 is a deficient number, since it is larger than the sum of its proper divisors (17233).

1866407 is a wasteful number, since it uses less digits than its factorization.

1866407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17232.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 1866407 is about 1366.1650705533. The cubic root of 1866407 is about 123.1219404532.

The spelling of 1866407 in words is "one million, eight hundred sixty-six thousand, four hundred seven".