201531 has 16 divisors (see below), whose sum is σ = 304128. Its totient is φ = 117600.

The previous prime is 201517. The next prime is 201547. The reversal of 201531 is 135102.

201531 = 85² + 86² + ... + 106².

It is not a de Polignac number, because 201531 - 2⁵ = 201499 is a prime.

It is a super-2 number, since 2×201531² = 81229487922, which contains 22 as substring.

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (201511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 925 + ... + 1121.

It is an arithmetic number, because the mean of its divisors is an integer number (19008).

2²⁰¹⁵³¹ is an apocalyptic number.

201531 is a deficient number, since it is larger than the sum of its proper divisors (102597).

201531 is a wasteful number, since it uses less digits than its factorization.

201531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242.

The product of its (nonzero) digits is 30, while the sum is 12.

The square root of 201531 is about 448.9220422301. The cubic root of 201531 is about 58.6291979815.

Adding to 201531 its reverse (135102), we get a palindrome (336633).

It can be divided in two parts, 20 and 1531, that added together give a palindrome (1551).

The spelling of 201531 in words is "two hundred one thousand, five hundred thirty-one".