278897238945 has 24 divisors (see below), whose sum is σ = 520608180456. Its totient is φ = 137303255808.

The previous prime is 278897238941. The next prime is 278897239001. The reversal of 278897238945 is 549832798872.

278897238945 is a `hidden beast` number, since 278 + 89 + 7 + 238 + 9 + 45 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 6879707136 + 272017531809 = 82944^2 + 521553^2 .

It is not a de Polignac number, because 278897238945 - 2² = 278897238941 is a prime.

It is a super-2 number, since 2×278897238945² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (278897238941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 238373124 + ... + 238374293.

It is an arithmetic number, because the mean of its divisors is an integer number (21692007519).

Almost surely, 2^278897238945 is an apocalyptic number.

It is an amenable number.

278897238945 is a deficient number, since it is larger than the sum of its proper divisors (241710941511).

278897238945 is a wasteful number, since it uses less digits than its factorization.

278897238945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476747441 (or 476747438 counting only the distinct ones).

The product of its digits is 487710720, while the sum is 72.

The spelling of 278897238945 in words is "two hundred seventy-eight billion, eight hundred ninety-seven million, two hundred thirty-eight thousand, nine hundred forty-five".