31520431421400 has 192 divisors, whose sum is σ = 99093770449920. Its totient is φ = 8286798873600.

The previous prime is 31520431421387. The next prime is 31520431421471. The reversal of 31520431421400 is 412413402513.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 104224405 + ... + 104526395.

It is an arithmetic number, because the mean of its divisors is an integer number (516113387760).

Almost surely, 2^{31520431421400} is an apocalyptic number.

31520431421400 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 31520431421400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49546885224960).

31520431421400 is an abundant number, since it is smaller than the sum of its proper divisors (67573339028520).

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

31520431421400 is a wasteful number, since it uses less digits than its factorization.

31520431421400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304466 (or 304457 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 30.

Adding to 31520431421400 its reverse (412413402513), we get a palindrome (31932844823913).

The spelling of 31520431421400 in words is "thirty-one trillion, five hundred twenty billion, four hundred thirty-one million, four hundred twenty-one thousand, four hundred".