1261978 has 8 divisors (see below), whose sum is σ = 2004372. Its totient is φ = 593856.

The previous prime is 1261973. The next prime is 1262011. The reversal of 1261978 is 8791621.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1216609 + 45369 = 1103^2 + 213^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (34), and also a Moran number because the ratio is a prime number: 37117 = 1261978 / (1 + 2 + 6 + 1 + 9 + 7 + 8).

It is not an unprimeable number, because it can be changed into a prime (1261973) 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, 18525 + ... + 18592.

2^1261978 is an apocalyptic number.

1261978 is a deficient number, since it is larger than the sum of its proper divisors (742394).

1261978 is a wasteful number, since it uses less digits than its factorization.

1261978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37136.

The product of its digits is 6048, while the sum is 34.

The square root of 1261978 is about 1123.3779417453. The cubic root of 1261978 is about 108.0647188684.

The spelling of 1261978 in words is "one million, two hundred sixty-one thousand, nine hundred seventy-eight".