1247661 has 6 divisors (see below), whose sum is σ = 1802190. Its totient is φ = 831768.

The previous prime is 1247651. The next prime is 1247663. The reversal of 1247661 is 1667421.

It can be written as a sum of positive squares in only one way, i.e., 1102500 + 145161 = 1050^2 + 381^2 .

It is not a de Polignac number, because 1247661 - 2¹¹ = 1245613 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1247663) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 69306 + ... + 69323.

It is an arithmetic number, because the mean of its divisors is an integer number (300365).

2^1247661 is an apocalyptic number.

It is an amenable number.

1247661 is a deficient number, since it is larger than the sum of its proper divisors (554529).

1247661 is a wasteful number, since it uses less digits than its factorization.

1247661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138635 (or 138632 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 1247661 is about 1116.9874663576. The cubic root of 1247661 is about 107.6545029130.

The spelling of 1247661 in words is "one million, two hundred forty-seven thousand, six hundred sixty-one".