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987 = 3747

987 has 8 divisors (see below), whose sum is σ = 1536. Its totient is φ = 552.

The previous prime is 983. The next prime is 991. The reversal of 987 is 789.

It is the 15-th Fibonacci number F15.

987 is nontrivially palindromic in base 11.

987 is an esthetic number in base 6 and base 10, because in such bases it adjacent digits differ by 1.

It is an interprime number because it is at equal distance from previous prime (983) and next prime (991).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 987 - 22 = 983 is a prime.

It is an alternating number because its digits alternate between odd and even.

987 is an undulating number in base 11.

It is a straight-line number, since its digits are in arithmetic progression.

It is a plaindrome in base 13 and base 15.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3 + ... + 44.

It is an arithmetic number, because the mean of its divisors is an integer number (192).

987 is a deficient number, since it is larger than the sum of its proper divisors (549).

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

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

The sum of its prime factors is 57.

The product of its digits is 504, while the sum is 24.

The square root of 987 is about 31.4165561448. The cubic root of 987 is about 9.9564775208.

The spelling of 987 in words is "nine hundred eighty-seven", and is thus an aban number and an oban number.

Divisors: 1 3 7 21 47 141 329 987