201531023 has 4 divisors (see below), whose sum is σ = 201640608. Its totient is φ = 201421440.

The previous prime is 201531019. The next prime is 201531049. The reversal of 201531023 is 320135102.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 201531023 - 2² = 201531019 is a prime.

It is a super-2 number, since 2×201531023² = 81229506462853058, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 201530992 and 201531010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201531013) 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 3 ways as a sum of consecutive naturals, for example, 51986 + ... + 55727.

It is an arithmetic number, because the mean of its divisors is an integer number (50410152).

Almost surely, 2^201531023 is an apocalyptic number.

201531023 is a deficient number, since it is larger than the sum of its proper divisors (109585).

201531023 is a wasteful number, since it uses less digits than its factorization.

201531023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109584.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 201531023 is about 14196.1622630907. The cubic root of 201531023 is about 586.2920021189.

Adding to 201531023 its reverse (320135102), we get a palindrome (521666125).

The spelling of 201531023 in words is "two hundred one million, five hundred thirty-one thousand, twenty-three".