1278621672 has 16 divisors (see below), whose sum is σ = 3196554240. Its totient is φ = 426207216.

The previous prime is 1278621653. The next prime is 1278621677. The reversal of 1278621672 is 2761268721.

It is not an unprimeable number, because it can be changed into a prime (1278621677) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26637928 + ... + 26637975.

It is an arithmetic number, because the mean of its divisors is an integer number (199784640).

Almost surely, 2^1278621672 is an apocalyptic number.

1278621672 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1278621672 is an abundant number, since it is smaller than the sum of its proper divisors (1917932568).

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

1278621672 is a wasteful number, since it uses less digits than its factorization.

1278621672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53275912 (or 53275908 counting only the distinct ones).

The product of its digits is 112896, while the sum is 42.

The square root of 1278621672 is about 35757.8197321928. The cubic root of 1278621672 is about 1085.3771818953.

The spelling of 1278621672 in words is "one billion, two hundred seventy-eight million, six hundred twenty-one thousand, six hundred seventy-two".