1278298505 has 32 divisors (see below), whose sum is σ = 1697251968. Its totient is φ = 916518400.

The previous prime is 1278298501. The next prime is 1278298513. The reversal of 1278298505 is 5058928721.

It is not a de Polignac number, because 1278298505 - 2² = 1278298501 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1278298505.

It is not an unprimeable number, because it can be changed into a prime (1278298501) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1653299 + ... + 1654071.

It is an arithmetic number, because the mean of its divisors is an integer number (53039124).

Almost surely, 2^1278298505 is an apocalyptic number.

It is an amenable number.

1278298505 is a deficient number, since it is larger than the sum of its proper divisors (418953463).

1278298505 is a wasteful number, since it uses less digits than its factorization.

1278298505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1177.

The product of its (nonzero) digits is 403200, while the sum is 47.

The square root of 1278298505 is about 35753.3006168661. The cubic root of 1278298505 is about 1085.2857324721.

The spelling of 1278298505 in words is "one billion, two hundred seventy-eight million, two hundred ninety-eight thousand, five hundred five".