1285380961 has 4 divisors (see below), whose sum is σ = 1285665172. Its totient is φ = 1285096752.

The previous prime is 1285380883. The next prime is 1285380977. The reversal of 1285380961 is 1690835821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 627201936 + 658179025 = 25044^2 + 25655^2 .

It is a cyclic number.

It is not a de Polignac number, because 1285380961 - 2¹⁹ = 1284856673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1285380361) 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, 135210 + ... + 144403.

It is an arithmetic number, because the mean of its divisors is an integer number (321416293).

Almost surely, 2^1285380961 is an apocalyptic number.

It is an amenable number.

1285380961 is a deficient number, since it is larger than the sum of its proper divisors (284211).

1285380961 is an equidigital number, since it uses as much as digits as its factorization.

1285380961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284210.

The product of its (nonzero) digits is 103680, while the sum is 43.

The square root of 1285380961 is about 35852.2099876702. The cubic root of 1285380961 is about 1087.2863961677.

The spelling of 1285380961 in words is "one billion, two hundred eighty-five million, three hundred eighty thousand, nine hundred sixty-one".