1321665061 has 8 divisors (see below), whose sum is σ = 1405570880. Its totient is φ = 1239193728.

The previous prime is 1321665047. The next prime is 1321665089. The reversal of 1321665061 is 1605661231.

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

It is a cyclic number.

It is not a de Polignac number, because 1321665061 - 2⁷ = 1321664933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321665001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 356721 + ... + 360406.

It is an arithmetic number, because the mean of its divisors is an integer number (175696360).

Almost surely, 2^1321665061 is an apocalyptic number.

It is an amenable number.

1321665061 is a deficient number, since it is larger than the sum of its proper divisors (83905819).

1321665061 is an equidigital number, since it uses as much as digits as its factorization.

1321665061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 717243.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 1321665061 is about 36354.7116753799. The cubic root of 1321665061 is about 1097.4223559519.

The spelling of 1321665061 in words is "one billion, three hundred twenty-one million, six hundred sixty-five thousand, sixty-one".