31487 has 6 divisors (see below), whose sum is σ = 33768. Its totient is φ = 29304.

The previous prime is 31481. The next prime is 31489. The reversal of 31487 is 78413.

It is a happy number.

It is not a de Polignac number, because 31487 - 2⁸ = 31231 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 833 + ... + 869.

It is an arithmetic number, because the mean of its divisors is an integer number (5628).

2³¹⁴⁸⁷ is an apocalyptic number.

31487 is a gapful number since it is divisible by the number (37) formed by its first and last digit.

31487 is a deficient number, since it is larger than the sum of its proper divisors (2281).

31487 is an equidigital number, since it uses as much as digits as its factorization.

31487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 60 counting only the distinct ones).

The product of its digits is 672, while the sum is 23.

The square root of 31487 is about 177.4457663626. The cubic root of 31487 is about 31.5774528045.

Multiplying 31487 by its sum of digits (23), we get a square (724201 = 851²).

31487 divided by its sum of digits (23) gives a square (1369 = 37²).

The spelling of 31487 in words is "thirty-one thousand, four hundred eighty-seven".