31438561280 has 448 divisors, whose sum is σ = 94366080000. Its totient is φ = 9809952768.

The previous prime is 31438561277. The next prime is 31438561291. The reversal of 31438561280 is 8216583413.

It is a tau number, because it is divible by the number of its divisors (448).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 157982621 + ... + 157982819.

Almost surely, 2^31438561280 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 31438561280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47183040000).

31438561280 is an abundant number, since it is smaller than the sum of its proper divisors (62927518720).

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

31438561280 is a wasteful number, since it uses less digits than its factorization.

31438561280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285 (or 261 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 41.

The spelling of 31438561280 in words is "thirty-one billion, four hundred thirty-eight million, five hundred sixty-one thousand, two hundred eighty".