31121020101011 has 4 divisors (see below), whose sum is σ = 32758968527400. Its totient is φ = 29483071674624.

The previous prime is 31121020100999. The next prime is 31121020101013. The reversal of 31121020101011 is 11010102012113.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31121020101011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31121020101013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 818974213166 + ... + 818974213203.

It is an arithmetic number, because the mean of its divisors is an integer number (8189742131850).

Almost surely, 2^{31121020101011} is an apocalyptic number.

31121020101011 is a deficient number, since it is larger than the sum of its proper divisors (1637948426389).

31121020101011 is a wasteful number, since it uses less digits than its factorization.

31121020101011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1637948426388.

The product of its (nonzero) digits is 12, while the sum is 14.

Adding to 31121020101011 its reverse (11010102012113), we get a palindrome (42131122113124).

The spelling of 31121020101011 in words is "thirty-one trillion, one hundred twenty-one billion, twenty million, one hundred one thousand, eleven".