278868669381 has 12 divisors (see below), whose sum is σ = 402937451020. Its totient is φ = 185853761280.

The previous prime is 278868669347. The next prime is 278868669389. The reversal of 278868669381 is 183966868872.

It can be written as a sum of positive squares in 2 ways, for example, as 187150546881 + 91718122500 = 432609^2 + 302850^2 .

It is not a de Polignac number, because 278868669381 - 2²³ = 278860280773 is a prime.

It is a super-2 number, since 2×278868669381² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (278868669389) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4860310 + ... + 4917351.

Almost surely, 2^278868669381 is an apocalyptic number.

It is an amenable number.

278868669381 is a deficient number, since it is larger than the sum of its proper divisors (124068781639).

278868669381 is a wasteful number, since it uses less digits than its factorization.

278868669381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9780836 (or 9780833 counting only the distinct ones).

The product of its digits is 334430208, while the sum is 72.

The spelling of 278868669381 in words is "two hundred seventy-eight billion, eight hundred sixty-eight million, six hundred sixty-nine thousand, three hundred eighty-one".