31242121400 has 96 divisors (see below), whose sum is σ = 83187056640. Its totient is φ = 10689356160.

The previous prime is 31242121397. The next prime is 31242121411. The reversal of 31242121400 is 412124213.

It is a Harshad number since it is a multiple of its sum of digits (20).

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 23 ways as a sum of consecutive naturals, for example, 658889 + ... + 704711.

It is an arithmetic number, because the mean of its divisors is an integer number (866531840).

Almost surely, 2^31242121400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31242121400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41593528320).

31242121400 is an abundant number, since it is smaller than the sum of its proper divisors (51944935240).

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

31242121400 is a wasteful number, since it uses less digits than its factorization.

31242121400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46333 (or 46324 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 31242121400 its reverse (412124213), we get a palindrome (31654245613).

The spelling of 31242121400 in words is "thirty-one billion, two hundred forty-two million, one hundred twenty-one thousand, four hundred".