31219049778 has 64 divisors (see below), whose sum is σ = 72493494528. Its totient is φ = 8778792960.

The previous prime is 31219049711. The next prime is 31219049861. The reversal of 31219049778 is 87794091213.

It is a self number, because there is not a number n which added to its sum of digits gives 31219049778.

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 31 ways as a sum of consecutive naturals, for example, 716226 + ... + 758562.

It is an arithmetic number, because the mean of its divisors is an integer number (1132710852).

Almost surely, 2^31219049778 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31219049778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36246747264).

31219049778 is an abundant number, since it is smaller than the sum of its proper divisors (41274444750).

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

31219049778 is a wasteful number, since it uses less digits than its factorization.

31219049778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42627.

The product of its (nonzero) digits is 762048, while the sum is 51.

The spelling of 31219049778 in words is "thirty-one billion, two hundred nineteen million, forty-nine thousand, seven hundred seventy-eight".