31123212520540 has 72 divisors (see below), whose sum is σ = 76031158805280. Its totient is φ = 10670591611008.

The previous prime is 31123212520537. The next prime is 31123212520571. The reversal of 31123212520540 is 4502521232113.

It is a happy number.

It is a super-3 number, since 3×31123212520540³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 50267166 + ... + 50882554.

It is an arithmetic number, because the mean of its divisors is an integer number (1055988316740).

Almost surely, 2^{31123212520540} is an apocalyptic number.

It is an amenable number.

31123212520540 is an abundant number, since it is smaller than the sum of its proper divisors (44907946284740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31123212520540 is a wasteful number, since it uses less digits than its factorization.

31123212520540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667019 (or 667010 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

Adding to 31123212520540 its reverse (4502521232113), we get a palindrome (35625733752653).

The spelling of 31123212520540 in words is "thirty-one trillion, one hundred twenty-three billion, two hundred twelve million, five hundred twenty thousand, five hundred forty".