31990430400 has 168 divisors, whose sum is σ = 107515816464. Its totient is φ = 8322662400.

The previous prime is 31990430393. The next prime is 31990430411. The reversal of 31990430400 is 403409913.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 115524 + ... + 278076.

It is an arithmetic number, because the mean of its divisors is an integer number (639975098).

Almost surely, 2^31990430400 is an apocalyptic number.

31990430400 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 31990430400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53757908232).

31990430400 is an abundant number, since it is smaller than the sum of its proper divisors (75525386064).

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

31990430400 is a wasteful number, since it uses less digits than its factorization.

31990430400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162619 (or 162604 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 33.

The spelling of 31990430400 in words is "thirty-one billion, nine hundred ninety million, four hundred thirty thousand, four hundred".