1281664139 has 24 divisors (see below), whose sum is σ = 1537207920. Its totient is φ = 1064980224.

The previous prime is 1281664129. The next prime is 1281664159. The reversal of 1281664139 is 9314661821.

It is not a de Polignac number, because 1281664139 - 2²⁰ = 1280615563 is a prime.

It is a super-2 number, since 2×1281664139² = 3285325930397222642, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1281664096 and 1281664105.

It is not an unprimeable number, because it can be changed into a prime (1281664129) 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 23 ways as a sum of consecutive naturals, for example, 208007 + ... + 214079.

It is an arithmetic number, because the mean of its divisors is an integer number (64050330).

Almost surely, 2^1281664139 is an apocalyptic number.

1281664139 is a deficient number, since it is larger than the sum of its proper divisors (255543781).

1281664139 is an equidigital number, since it uses as much as digits as its factorization.

1281664139 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6219 (or 6212 counting only the distinct ones).

The product of its digits is 62208, while the sum is 41.

The square root of 1281664139 is about 35800.3371352841. The cubic root of 1281664139 is about 1086.2373812242.

The spelling of 1281664139 in words is "one billion, two hundred eighty-one million, six hundred sixty-four thousand, one hundred thirty-nine".