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31375 = 53251
BaseRepresentation
bin111101010001111
31121001001
413222033
52001000
6401131
7160321
oct75217
947031
1031375
1121633
12161a7
1311386
14b611
15946a
hex7a8f

31375 has 8 divisors (see below), whose sum is σ = 39312. Its totient is φ = 25000.

The previous prime is 31357. The next prime is 31379. The reversal of 31375 is 57313.

31375 is a nontrivial binomial coefficient, being equal to C(251, 2).

It is not a de Polignac number, because 31375 - 27 = 31247 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31379) 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, 1 + ... + 250.

It is an arithmetic number, because the mean of its divisors is an integer number (4914).

231375 is an apocalyptic number.

31375 is the 250-th triangular number.

31375 is the 84-th centered nonagonal number.

31375 is a deficient number, since it is larger than the sum of its proper divisors (7937).

31375 is an equidigital number, since it uses as much as digits as its factorization.

31375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266 (or 256 counting only the distinct ones).

The product of its digits is 315, while the sum is 19.

The square root of 31375 is about 177.1298958392. The cubic root of 31375 is about 31.5399677433.

Adding to 31375 its reverse (57313), we get a palindrome (88688).

It can be divided in two parts, 31 and 375, that added together give a triangular number (406 = T28).

The spelling of 31375 in words is "thirty-one thousand, three hundred seventy-five".

Divisors: 1 5 25 125 251 1255 6275 31375