1275661 has 2 divisors, whose sum is σ = 1275662. Its totient is φ = 1275660.

The previous prime is 1275643. The next prime is 1275667. The reversal of 1275661 is 1665721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 828100 + 447561 = 910^2 + 669^2 .

It is a cyclic number.

It is not a de Polignac number, because 1275661 - 2¹⁵ = 1242893 is a prime.

1275661 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1275667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 637830 + 637831.

It is an arithmetic number, because the mean of its divisors is an integer number (637831).

2^1275661 is an apocalyptic number.

It is an amenable number.

1275661 is a deficient number, since it is larger than the sum of its proper divisors (1).

1275661 is an equidigital number, since it uses as much as digits as its factorization.

1275661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2520, while the sum is 28.

The square root of 1275661 is about 1129.4516368575. The cubic root of 1275661 is about 108.4538797521.

It can be divided in two parts, 1275 and 661, that added together give a square (1936 = 44²).

The spelling of 1275661 in words is "one million, two hundred seventy-five thousand, six hundred sixty-one".