31078977864 has 64 divisors (see below), whose sum is σ = 84900925440. Its totient is φ = 9402308160.

The previous prime is 31078977851. The next prime is 31078977869. The reversal of 31078977864 is 46877987013.

It is a junction number, because it is equal to n+sod(n) for n = 31078977798 and 31078977807.

It is not an unprimeable number, because it can be changed into a prime (31078977869) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 63277 + ... + 257219.

It is an arithmetic number, because the mean of its divisors is an integer number (1326576960).

Almost surely, 2^31078977864 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 31078977864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42450462720).

31078977864 is an abundant number, since it is smaller than the sum of its proper divisors (53821947576).

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

31078977864 is a wasteful number, since it uses less digits than its factorization.

31078977864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194570 (or 194566 counting only the distinct ones).

The product of its (nonzero) digits is 14224896, while the sum is 60.

The spelling of 31078977864 in words is "thirty-one billion, seventy-eight million, nine hundred seventy-seven thousand, eight hundred sixty-four".