31505143104 has 280 divisors, whose sum is σ = 99307086120. Its totient is φ = 9875976192.

The previous prime is 31505143099. The next prime is 31505143123. The reversal of 31505143104 is 40134150513.

It is a happy number.

31505143104 is a `hidden beast` number, since 3 + 1 + 505 + 143 + 10 + 4 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 9377985600 + 22127157504 = 96840^2 + 148752^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 25468374 + ... + 25469610.

Almost surely, 2^31505143104 is an apocalyptic number.

31505143104 is a gapful number since it is divisible by the number (34) 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 31505143104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49653543060).

31505143104 is an abundant number, since it is smaller than the sum of its proper divisors (67801943016).

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

31505143104 is an equidigital number, since it uses as much as digits as its factorization.

31505143104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1312 (or 1259 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

Adding to 31505143104 its reverse (40134150513), we get a palindrome (71639293617).

The spelling of 31505143104 in words is "thirty-one billion, five hundred five million, one hundred forty-three thousand, one hundred four".