1278579540 has 288 divisors, whose sum is σ = 4486164480. Its totient is φ = 270418176.

The previous prime is 1278579539. The next prime is 1278579541. The reversal of 1278579540 is 459758721.

It is an interprime number because it is at equal distance from previous prime (1278579539) and next prime (1278579541).

It is a super-2 number, since 2×1278579540² = 3269531280213223200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1278579540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1278579541) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2625177 + ... + 2625663.

It is an arithmetic number, because the mean of its divisors is an integer number (15576960).

Almost surely, 2^1278579540 is an apocalyptic number.

1278579540 is a gapful number since it is divisible by the number (10) 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 1278579540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2243082240).

1278579540 is an abundant number, since it is smaller than the sum of its proper divisors (3207584940).

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

1278579540 is a wasteful number, since it uses less digits than its factorization.

1278579540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 579 (or 570 counting only the distinct ones).

The product of its (nonzero) digits is 705600, while the sum is 48.

The square root of 1278579540 is about 35757.2305974610. The cubic root of 1278579540 is about 1085.3652603043.

The spelling of 1278579540 in words is "one billion, two hundred seventy-eight million, five hundred seventy-nine thousand, five hundred forty".