1287211650 has 24 divisors (see below), whose sum is σ = 3192285264. Its totient is φ = 343256400.

The previous prime is 1287211649. The next prime is 1287211657. The reversal of 1287211650 is 561127821.

It is not an unprimeable number, because it can be changed into a prime (1287211657) 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 11 ways as a sum of consecutive naturals, for example, 4290556 + ... + 4290855.

It is an arithmetic number, because the mean of its divisors is an integer number (133011886).

Almost surely, 2^1287211650 is an apocalyptic number.

1287211650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1287211650 is an abundant number, since it is smaller than the sum of its proper divisors (1905073614).

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

1287211650 is a wasteful number, since it uses less digits than its factorization.

1287211650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8581426 (or 8581421 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 33.

The square root of 1287211650 is about 35877.7319517274. The cubic root of 1287211650 is about 1087.8023363386.

The spelling of 1287211650 in words is "one billion, two hundred eighty-seven million, two hundred eleven thousand, six hundred fifty".