278631648 has 72 divisors (see below), whose sum is σ = 794593800. Its totient is φ = 92615424.

The previous prime is 278631611. The next prime is 278631673. The reversal of 278631648 is 846136872.

278631648 is a `hidden beast` number, since 2 + 7 + 8 + 631 + 6 + 4 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a nialpdrome in base 7.

It is a zygodrome in base 7.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 119518 + ... + 121826.

It is an arithmetic number, because the mean of its divisors is an integer number (11036025).

Almost surely, 2^278631648 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 278631648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (397296900).

278631648 is an abundant number, since it is smaller than the sum of its proper divisors (515962152).

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

278631648 is a wasteful number, since it uses less digits than its factorization.

278631648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2744 (or 2733 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 278631648 is about 16692.2631179837. The cubic root of 278631648 is about 653.1458141089.

The spelling of 278631648 in words is "two hundred seventy-eight million, six hundred thirty-one thousand, six hundred forty-eight".