1261557 has 12 divisors (see below), whose sum is σ = 1988064. Its totient is φ = 764520.

The previous prime is 1261549. The next prime is 1261567. The reversal of 1261557 is 7551621.

It is not a de Polignac number, because 1261557 - 2³ = 1261549 is a prime.

1261557 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1261557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261567) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6273 + ... + 6470.

It is an arithmetic number, because the mean of its divisors is an integer number (165672).

2^1261557 is an apocalyptic number.

It is an amenable number.

1261557 is a deficient number, since it is larger than the sum of its proper divisors (726507).

1261557 is a wasteful number, since it uses less digits than its factorization.

1261557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12760 (or 12757 counting only the distinct ones).

The product of its digits is 2100, while the sum is 27.

The square root of 1261557 is about 1123.1905448320. The cubic root of 1261557 is about 108.0527006170.

Subtracting 1261557 from its reverse (7551621), we obtain a square (6290064 = 2508²).

The spelling of 1261557 in words is "one million, two hundred sixty-one thousand, five hundred fifty-seven".