1278966780 has 384 divisors, whose sum is σ = 5188700160. Its totient is φ = 253808640.

The previous prime is 1278966769. The next prime is 1278966781. The reversal of 1278966780 is 876698721.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1278966781) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 834615 + ... + 836145.

It is an arithmetic number, because the mean of its divisors is an integer number (13512240).

Almost surely, 2^1278966780 is an apocalyptic number.

1278966780 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 1278966780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2594350080).

1278966780 is an abundant number, since it is smaller than the sum of its proper divisors (3909733380).

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

1278966780 is a wasteful number, since it uses less digits than its factorization.

1278966780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1586 (or 1578 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The square root of 1278966780 is about 35762.6450364064. The cubic root of 1278966780 is about 1085.4748231449.

The spelling of 1278966780 in words is "one billion, two hundred seventy-eight million, nine hundred sixty-six thousand, seven hundred eighty".