31131231103121 has 16 divisors (see below), whose sum is σ = 32157466272768. Its totient is φ = 30106375488000.

The previous prime is 31131231103117. The next prime is 31131231103177. The reversal of 31131231103121 is 12130113213113.

It is a cyclic number.

It is not a de Polignac number, because 31131231103121 - 2² = 31131231103117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31131231183121) 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, 491671961 + ... + 491735273.

It is an arithmetic number, because the mean of its divisors is an integer number (2009841642048).

Almost surely, 2^{31131231103121} is an apocalyptic number.

31131231103121 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

31131231103121 is a deficient number, since it is larger than the sum of its proper divisors (1026235169647).

31131231103121 is a wasteful number, since it uses less digits than its factorization.

31131231103121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73952.

The product of its (nonzero) digits is 324, while the sum is 23.

Adding to 31131231103121 its reverse (12130113213113), we get a palindrome (43261344316234).

The spelling of 31131231103121 in words is "thirty-one trillion, one hundred thirty-one billion, two hundred thirty-one million, one hundred three thousand, one hundred twenty-one".