1280273640 has 32 divisors (see below), whose sum is σ = 3840821280. Its totient is φ = 341406272.

The previous prime is 1280273569. The next prime is 1280273641. The reversal of 1280273640 is 463720821.

It is not an unprimeable number, because it can be changed into a prime (1280273641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5334354 + ... + 5334593.

It is an arithmetic number, because the mean of its divisors is an integer number (120025665).

Almost surely, 2^1280273640 is an apocalyptic number.

1280273640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1280273640 is an abundant number, since it is smaller than the sum of its proper divisors (2560547640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1280273640 is a wasteful number, since it uses less digits than its factorization.

1280273640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10668961 (or 10668957 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 1280273640 is about 35780.9116708895. The cubic root of 1280273640 is about 1085.8444133372.

The spelling of 1280273640 in words is "one billion, two hundred eighty million, two hundred seventy-three thousand, six hundred forty".