278145323820 has 576 divisors, whose sum is σ = 1092761026560. Its totient is φ = 58214370816.

The previous prime is 278145323789. The next prime is 278145323821. The reversal of 278145323820 is 28323541872.

278145323820 is a `hidden beast` number, since 2 + 7 + 81 + 4 + 532 + 38 + 2 + 0 = 666.

278145323820 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (278145323821) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 43682277 + ... + 43688643.

It is an arithmetic number, because the mean of its divisors is an integer number (1897154560).

Almost surely, 2^278145323820 is an apocalyptic number.

278145323820 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 278145323820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (546380513280).

278145323820 is an abundant number, since it is smaller than the sum of its proper divisors (814615702740).

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

278145323820 is a wasteful number, since it uses less digits than its factorization.

278145323820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6539 (or 6524 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

The spelling of 278145323820 in words is "two hundred seventy-eight billion, one hundred forty-five million, three hundred twenty-three thousand, eight hundred twenty".