31121012102 has 4 divisors (see below), whose sum is σ = 46681518156. Its totient is φ = 15560506050.

The previous prime is 31121012101. The next prime is 31121012113. The reversal of 31121012102 is 20121012113.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 20121012113 = 41 ⋅490756393.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31121012101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7780253024 + ... + 7780253027.

It is an arithmetic number, because the mean of its divisors is an integer number (11670379539).

Almost surely, 2^31121012102 is an apocalyptic number.

31121012102 is a deficient number, since it is larger than the sum of its proper divisors (15560506054).

31121012102 is a wasteful number, since it uses less digits than its factorization.

31121012102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15560506053.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 31121012102 its reverse (20121012113), we get a palindrome (51242024215).

The spelling of 31121012102 in words is "thirty-one billion, one hundred twenty-one million, twelve thousand, one hundred two".