278161920 has 120 divisors (see below), whose sum is σ = 963432756. Its totient is φ = 74170368.

The previous prime is 278161913. The next prime is 278161937. The reversal of 278161920 is 29161872.

It can be written as a sum of positive squares in 2 ways, for example, as 237406464 + 40755456 = 15408^2 + 6384^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 17004 + ... + 29076.

Almost surely, 2^278161920 is an apocalyptic number.

278161920 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 278161920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (481716378).

278161920 is an abundant number, since it is smaller than the sum of its proper divisors (685270836).

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

278161920 is a wasteful number, since it uses less digits than its factorization.

278161920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12102 (or 12083 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 278161920 is about 16678.1869518242. The cubic root of 278161920 is about 652.7785748447.

The spelling of 278161920 in words is "two hundred seventy-eight million, one hundred sixty-one thousand, nine hundred twenty".