1280401005 has 32 divisors (see below), whose sum is σ = 2208600576. Its totient is φ = 629673984.

The previous prime is 1280400997. The next prime is 1280401033. The reversal of 1280401005 is 5001040821.

It is not a de Polignac number, because 1280401005 - 2³ = 1280400997 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 212109 + ... + 218061.

It is an arithmetic number, because the mean of its divisors is an integer number (69018768).

Almost surely, 2^1280401005 is an apocalyptic number.

1280401005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1280401005 is a deficient number, since it is larger than the sum of its proper divisors (928199571).

1280401005 is a wasteful number, since it uses less digits than its factorization.

1280401005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7077.

The product of its (nonzero) digits is 320, while the sum is 21.

The square root of 1280401005 is about 35782.6914163817. The cubic root of 1280401005 is about 1085.8804196990.

Adding to 1280401005 its reverse (5001040821), we get a palindrome (6281441826).

The spelling of 1280401005 in words is "one billion, two hundred eighty million, four hundred one thousand, five".