1321078005 has 48 divisors (see below), whose sum is σ = 2557376640. Its totient is φ = 650369088.

The previous prime is 1321077971. The next prime is 1321078013. The reversal of 1321078005 is 5008701231.

It is not a de Polignac number, because 1321078005 - 2⁶ = 1321077941 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 1321078005.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 26025 + ... + 57614.

It is an arithmetic number, because the mean of its divisors is an integer number (53278680).

Almost surely, 2^1321078005 is an apocalyptic number.

1321078005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1321078005 is a deficient number, since it is larger than the sum of its proper divisors (1236298635).

1321078005 is an equidigital number, since it uses as much as digits as its factorization.

1321078005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83672 (or 83660 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 1321078005 is about 36346.6367770114. The cubic root of 1321078005 is about 1097.2598478631.

Adding to 1321078005 its reverse (5008701231), we get a palindrome (6329779236).

The spelling of 1321078005 in words is "one billion, three hundred twenty-one million, seventy-eight thousand, five".