31540203121 has 16 divisors (see below), whose sum is σ = 36641721600. Its totient is φ = 26589696768.

The previous prime is 31540203089. The next prime is 31540203131. The reversal of 31540203121 is 12130204513.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 31540203121 - 2⁵ = 31540203089 is a prime.

It is a super-3 number, since 3×31540203121³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31540203092 and 31540203101.

It is not an unprimeable number, because it can be changed into a prime (31540203131) 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, 97485 + ... + 269413.

It is an arithmetic number, because the mean of its divisors is an integer number (2290107600).

Almost surely, 2^31540203121 is an apocalyptic number.

It is an amenable number.

31540203121 is a deficient number, since it is larger than the sum of its proper divisors (5101518479).

31540203121 is a wasteful number, since it uses less digits than its factorization.

31540203121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172368.

The product of its (nonzero) digits is 720, while the sum is 22.

Adding to 31540203121 its reverse (12130204513), we get a palindrome (43670407634).

The spelling of 31540203121 in words is "thirty-one billion, five hundred forty million, two hundred three thousand, one hundred twenty-one".