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BaseRepresentation
bin100111000000001000100
32101221010002
410320001010
5311344040
643220432
713602002
oct4700104
92357102
101278020
117a3217
12517718
13359933
14253a72
151a3a15
hex138044

1278020 has 12 divisors (see below), whose sum is σ = 2683884. Its totient is φ = 511200.

The previous prime is 1278007. The next prime is 1278029. The reversal of 1278020 is 208721.

It can be written as a sum of positive squares in 2 ways, for example, as 891136 + 386884 = 944^2 + 622^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 63901 = 1278020 / (1 + 2 + 7 + 8 + 0 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 1277983 and 1278001.

It is not an unprimeable number, because it can be changed into a prime (1278029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31931 + ... + 31970.

It is an arithmetic number, because the mean of its divisors is an integer number (223657).

21278020 is an apocalyptic number.

1278020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1278020 is an abundant number, since it is smaller than the sum of its proper divisors (1405864).

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

1278020 is a wasteful number, since it uses less digits than its factorization.

1278020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63910 (or 63908 counting only the distinct ones).

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

The square root of 1278020 is about 1130.4954665986. The cubic root of 1278020 is about 108.5206909084.

The spelling of 1278020 in words is "one million, two hundred seventy-eight thousand, twenty".