1278777456 has 200 divisors, whose sum is σ = 4064763648. Its totient is φ = 384912000.

The previous prime is 1278777439. The next prime is 1278777469. The reversal of 1278777456 is 6547778721.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 3863211 + ... + 3863541.

Almost surely, 2^1278777456 is an apocalyptic number.

1278777456 is a gapful number since it is divisible by the number (16) 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 1278777456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2032381824).

1278777456 is an abundant number, since it is smaller than the sum of its proper divisors (2785986192).

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

1278777456 is a wasteful number, since it uses less digits than its factorization.

1278777456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633 (or 618 counting only the distinct ones).

The product of its digits is 4609920, while the sum is 54.

The square root of 1278777456 is about 35759.9979865771. The cubic root of 1278777456 is about 1085.4212599668.

The spelling of 1278777456 in words is "one billion, two hundred seventy-eight million, seven hundred seventy-seven thousand, four hundred fifty-six".