1287864000 has 336 divisors, whose sum is σ = 4763755776. Its totient is φ = 331776000.

The previous prime is 1287863989. The next prime is 1287864077. The reversal of 1287864000 is 4687821.

1287864000 is a `hidden beast` number, since 1 + 2 + 8 + 7 + 8 + 640 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2231712 + ... + 2232288.

Almost surely, 2^1287864000 is an apocalyptic number.

1287864000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1287864000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2381877888).

1287864000 is an abundant number, since it is smaller than the sum of its proper divisors (3475891776).

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

1287864000 is a wasteful number, since it uses less digits than its factorization.

1287864000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 641 (or 618 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 1287864000 is about 35886.8220939107. The cubic root of 1287864000 is about 1087.9860688816.

The spelling of 1287864000 in words is "one billion, two hundred eighty-seven million, eight hundred sixty-four thousand".