1287183820 has 24 divisors (see below), whose sum is σ = 2911016304. Its totient is φ = 475267776.

The previous prime is 1287183797. The next prime is 1287183827. The reversal of 1287183820 is 283817821.

It is not an unprimeable number, because it can be changed into a prime (1287183827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2475094 + ... + 2475613.

It is an arithmetic number, because the mean of its divisors is an integer number (121292346).

Almost surely, 2^1287183820 is an apocalyptic number.

1287183820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1287183820 is an abundant number, since it is smaller than the sum of its proper divisors (1623832484).

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

1287183820 is a wasteful number, since it uses less digits than its factorization.

1287183820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4950729 (or 4950727 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 40.

The square root of 1287183820 is about 35877.3441046017. The cubic root of 1287183820 is about 1087.7944967168.

The spelling of 1287183820 in words is "one billion, two hundred eighty-seven million, one hundred eighty-three thousand, eight hundred twenty".