1320639278 has 48 divisors (see below), whose sum is σ = 2357228160. Its totient is φ = 553147056.

The previous prime is 1320639247. The next prime is 1320639301. The reversal of 1320639278 is 8729360231.

It is a super-2 number, since 2×1320639278² = 3488176205192722568, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 911951 + ... + 913397.

It is an arithmetic number, because the mean of its divisors is an integer number (49108920).

Almost surely, 2^1320639278 is an apocalyptic number.

1320639278 is a deficient number, since it is larger than the sum of its proper divisors (1036588882).

1320639278 is a wasteful number, since it uses less digits than its factorization.

1320639278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1669 (or 1662 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 41.

The square root of 1320639278 is about 36340.6009581570. The cubic root of 1320639278 is about 1097.1383685813.

The spelling of 1320639278 in words is "one billion, three hundred twenty million, six hundred thirty-nine thousand, two hundred seventy-eight".