31121211030 has 128 divisors (see below), whose sum is σ = 92016304128. Its totient is φ = 6559875072.

The previous prime is 31121210993. The next prime is 31121211047. The reversal of 31121211030 is 3011212113.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3142747 + ... + 3152633.

It is an arithmetic number, because the mean of its divisors is an integer number (718877376).

Almost surely, 2^31121211030 is an apocalyptic number.

31121211030 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 31121211030, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46008152064).

31121211030 is an abundant number, since it is smaller than the sum of its proper divisors (60895093098).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31121211030 is a wasteful number, since it uses less digits than its factorization.

31121211030 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11070.

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 31121211030 its reverse (3011212113), we get a palindrome (34132423143).

The spelling of 31121211030 in words is "thirty-one billion, one hundred twenty-one million, two hundred eleven thousand, thirty".