278887760640 has 288 divisors, whose sum is σ = 998436277440. Its totient is φ = 73710895104.

The previous prime is 278887760633. The next prime is 278887760651. The reversal of 278887760640 is 46067788872.

It is a tau number, because it is divible by the number of its divisors (288).

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, 3869574 + ... + 3940986.

It is an arithmetic number, because the mean of its divisors is an integer number (3466792630).

Almost surely, 2^278887760640 is an apocalyptic number.

278887760640 is a gapful number since it is divisible by the number (20) 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 278887760640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (499218138720).

278887760640 is an abundant number, since it is smaller than the sum of its proper divisors (719548516800).

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

278887760640 is a wasteful number, since it uses less digits than its factorization.

278887760640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71556 (or 71536 counting only the distinct ones).

The product of its (nonzero) digits is 50577408, while the sum is 63.

The spelling of 278887760640 in words is "two hundred seventy-eight billion, eight hundred eighty-seven million, seven hundred sixty thousand, six hundred forty".