1287020 has 48 divisors (see below), whose sum is σ = 3205440. Its totient is φ = 424704.

The previous prime is 1287007. The next prime is 1287047. The reversal of 1287020 is 207821.

1287020 = T₁₈₁ + T₁₈₂ + ... + T₂₃₈.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1286983 and 1287001.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3902 + ... + 4218.

It is an arithmetic number, because the mean of its divisors is an integer number (66780).

2^1287020 is an apocalyptic number.

1287020 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 1287020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1602720).

1287020 is an abundant number, since it is smaller than the sum of its proper divisors (1918420).

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

1287020 is a wasteful number, since it uses less digits than its factorization.

1287020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362 (or 360 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 20.

The square root of 1287020 is about 1134.4690388019. The cubic root of 1287020 is about 108.7748346858.

The spelling of 1287020 in words is "one million, two hundred eighty-seven thousand, twenty".