1245661 has 4 divisors (see below), whose sum is σ = 1252800. Its totient is φ = 1238524.

The previous prime is 1245649. The next prime is 1245683. The reversal of 1245661 is 1665421.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1245661 - 2⁹ = 1245149 is a prime.

It is an Ulam number.

It is a Duffinian number.

1245661 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1245691) 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, 3301 + ... + 3658.

It is an arithmetic number, because the mean of its divisors is an integer number (313200).

2^1245661 is an apocalyptic number.

It is an amenable number.

1245661 is a deficient number, since it is larger than the sum of its proper divisors (7139).

1245661 is an equidigital number, since it uses as much as digits as its factorization.

1245661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7138.

The product of its digits is 1440, while the sum is 25.

The square root of 1245661 is about 1116.0918420990. The cubic root of 1245661 is about 107.5969487764.

The spelling of 1245661 in words is "one million, two hundred forty-five thousand, six hundred sixty-one".