31115120551221 has 12 divisors (see below), whose sum is σ = 48260186977632. Its totient is φ = 17780068886328.

The previous prime is 31115120551213. The next prime is 31115120551241. The reversal of 31115120551221 is 12215502151113.

It is not a de Polignac number, because 31115120551221 - 2³ = 31115120551213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31115120551241) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 105833743225 + ... + 105833743518.

It is an arithmetic number, because the mean of its divisors is an integer number (4021682248136).

Almost surely, 2^{31115120551221} is an apocalyptic number.

It is an amenable number.

31115120551221 is a deficient number, since it is larger than the sum of its proper divisors (17145066426411).

31115120551221 is a wasteful number, since it uses less digits than its factorization.

31115120551221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211667486760 (or 211667486753 counting only the distinct ones).

The product of its (nonzero) digits is 3000, while the sum is 30.

The spelling of 31115120551221 in words is "thirty-one trillion, one hundred fifteen billion, one hundred twenty million, five hundred fifty-one thousand, two hundred twenty-one".