1305720 has 160 divisors (see below), whose sum is σ = 4878720.
Its totient is φ = 311040.
The previous prime is 1305713. The next prime is 1305739. The reversal of 1305720 is 275031.
It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.
It is a Harshad number since it is a multiple of its sum of digits (18).
It is a junction number, because it is equal to n+sod(n) for n = 1305693 and 1305702.
It is a congruent number.
It is an unprimeable number.
It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 42105 + ... + 42135.
It is an arithmetic number, because the mean of its divisors is an integer number (30492).
21305720 is an apocalyptic number.
1305720 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 1305720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2439360).
1305720 is an abundant number, since it is smaller than the sum of its proper divisors (3573000).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
1305720 is a wasteful number, since it uses less digits than its factorization.
1305720 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 67 (or 54 counting only the distinct ones).
The product of its (nonzero) digits is 210, while the sum is 18.
The square root of 1305720 is about 1142.6810578635.
The cubic root of 1305720 is about 109.2991250638.
It can be divided in two parts, 1305 and 720, that added together give a square (2025 = 452).
The spelling of 1305720 in words is "one million, three hundred five thousand, seven hundred twenty".