1263661 has 24 divisors (see below), whose sum is σ = 1637496. Its totient is φ = 967680.

The previous prime is 1263659. The next prime is 1263667. The reversal of 1263661 is 1663621.

It can be written as a sum of positive squares in 4 ways, for example, as 275625 + 988036 = 525^2 + 994^2 .

It is not a de Polignac number, because 1263661 - 2¹ = 1263659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1263667) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 30801 + ... + 30841.

It is an arithmetic number, because the mean of its divisors is an integer number (68229).

2^1263661 is an apocalyptic number.

It is an amenable number.

1263661 is a deficient number, since it is larger than the sum of its proper divisors (373835).

1263661 is a wasteful number, since it uses less digits than its factorization.

1263661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109 (or 102 counting only the distinct ones).

The product of its digits is 1296, while the sum is 25.

The square root of 1263661 is about 1124.1267722103. The cubic root of 1263661 is about 108.1127366447.

The spelling of 1263661 in words is "one million, two hundred sixty-three thousand, six hundred sixty-one".