31000320000 has 1200 divisors, whose sum is σ = 130025815920. Its totient is φ = 7299072000.

The previous prime is 31000319989. The next prime is 31000320031. The reversal of 31000320000 is 2300013.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1200).

It is a super-2 number, since 2×31000320000² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 99 ways as a sum of consecutive naturals, for example, 1347839989 + ... + 1347840011.

Almost surely, 2^31000320000 is an apocalyptic number.

31000320000 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31000320000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65012907960).

31000320000 is an abundant number, since it is smaller than the sum of its proper divisors (99025495920).

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

31000320000 is an equidigital number, since it uses as much as digits as its factorization.

31000320000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 9.

Adding to 31000320000 its reverse (2300013), we get a palindrome (31002620013).

The spelling of 31000320000 in words is "thirty-one billion, three hundred twenty thousand".