1206551 has 4 divisors (see below), whose sum is σ = 1245504. Its totient is φ = 1167600.

The previous prime is 1206539. The next prime is 1206553. The reversal of 1206551 is 1556021.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1556021 = 103 ⋅15107.

It is a cyclic number.

It is not a de Polignac number, because 1206551 - 2¹⁰ = 1205527 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 (1206553) 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, 19430 + ... + 19491.

It is an arithmetic number, because the mean of its divisors is an integer number (311376).

2^1206551 is an apocalyptic number.

1206551 is a deficient number, since it is larger than the sum of its proper divisors (38953).

1206551 is an equidigital number, since it uses as much as digits as its factorization.

1206551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38952.

The product of its (nonzero) digits is 300, while the sum is 20.

The square root of 1206551 is about 1098.4311539646. The cubic root of 1206551 is about 106.4588804353.

The spelling of 1206551 in words is "one million, two hundred six thousand, five hundred fifty-one".