278890001 has 8 divisors (see below), whose sum is σ = 300542760. Its totient is φ = 257265792.

The previous prime is 278889983. The next prime is 278890021. The reversal of 278890001 is 100098872.

It is a happy number.

It is a Cunningham number, because it is equal to 16700²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 41267776 + 237622225 = 6424^2 + 15415^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 278890001 - 2⁶ = 278889937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (278890021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15941 + ... + 28493.

It is an arithmetic number, because the mean of its divisors is an integer number (37567845).

Almost surely, 2^278890001 is an apocalyptic number.

It is an amenable number.

278890001 is a deficient number, since it is larger than the sum of its proper divisors (21652759).

278890001 is a wasteful number, since it uses less digits than its factorization.

278890001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14275.

The product of its (nonzero) digits is 8064, while the sum is 35.

The square root of 278890001 is about 16700.0000299401. Note that the first 4 decimals coincide. The cubic root of 278890001 is about 653.3476218299.

The spelling of 278890001 in words is "two hundred seventy-eight million, eight hundred ninety thousand, one".