278839744304640 has 640 divisors, whose sum is σ = 980608834732032. Its totient is φ = 67365476597760.

The previous prime is 278839744304623. The next prime is 278839744304657. The reversal of 278839744304640 is 46403447938872.

It is an interprime number because it is at equal distance from previous prime (278839744304623) and next prime (278839744304657).

It is a tau number, because it is divible by the number of its divisors (640).

It is a Smith number, since the sum of its digits (69) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (69).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 256822759 + ... + 257906201.

Almost surely, 2^{278839744304640} is an apocalyptic number.

278839744304640 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 278839744304640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (490304417366016).

278839744304640 is an abundant number, since it is smaller than the sum of its proper divisors (701769090427392).

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

278839744304640 is a wasteful number, since it uses less digits than its factorization.

278839744304640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1083570 (or 1083554 counting only the distinct ones).

The product of its (nonzero) digits is 780337152, while the sum is 69.

The spelling of 278839744304640 in words is "two hundred seventy-eight trillion, eight hundred thirty-nine billion, seven hundred forty-four million, three hundred four thousand, six hundred forty".