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1087681 = 7155383
BaseRepresentation
bin100001001100011000001
32001021000111
410021203001
5234301211
635151321
712150040
oct4114301
92037014
101087681
11683211
12445541
132c10ca
14204557
15167421
hex1098c1

1087681 has 4 divisors (see below), whose sum is σ = 1243072. Its totient is φ = 932292.

The previous prime is 1087679. The next prime is 1087687. The reversal of 1087681 is 1867801.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1867801 = 13143677.

It is a cyclic number.

It is not a de Polignac number, because 1087681 - 21 = 1087679 is a prime.

It is a super-2 number, since 2×10876812 = 2366099915522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1087687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 77685 + ... + 77698.

It is an arithmetic number, because the mean of its divisors is an integer number (310768).

21087681 is an apocalyptic number.

It is an amenable number.

1087681 is a deficient number, since it is larger than the sum of its proper divisors (155391).

1087681 is an equidigital number, since it uses as much as digits as its factorization.

1087681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155390.

The product of its (nonzero) digits is 2688, while the sum is 31.

The square root of 1087681 is about 1042.9194599776. The cubic root of 1087681 is about 102.8412106973.

The spelling of 1087681 in words is "one million, eighty-seven thousand, six hundred eighty-one".

Divisors: 1 7 155383 1087681