31155231103 has 4 divisors (see below), whose sum is σ = 31192904520. Its totient is φ = 31117557688.

The previous prime is 31155231059. The next prime is 31155231113. The reversal of 31155231103 is 30113255113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30113255113 = 97 ⋅310445929.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31155231103 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31155231113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18835468 + ... + 18837121.

It is an arithmetic number, because the mean of its divisors is an integer number (7798226130).

Almost surely, 2^31155231103 is an apocalyptic number.

31155231103 is a deficient number, since it is larger than the sum of its proper divisors (37673417).

31155231103 is an equidigital number, since it uses as much as digits as its factorization.

31155231103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37673416.

The product of its (nonzero) digits is 1350, while the sum is 25.

Adding to 31155231103 its reverse (30113255113), we get a palindrome (61268486216).

The spelling of 31155231103 in words is "thirty-one billion, one hundred fifty-five million, two hundred thirty-one thousand, one hundred three".