1281971979 has 12 divisors (see below), whose sum is σ = 1853274696. Its totient is φ = 853938432.

The previous prime is 1281971959. The next prime is 1281971987. The reversal of 1281971979 is 9791791821.

It is not a de Polignac number, because 1281971979 - 2⁷ = 1281971851 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1281971959) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 47569 + ... + 69474.

It is an arithmetic number, because the mean of its divisors is an integer number (154439558).

Almost surely, 2^1281971979 is an apocalyptic number.

1281971979 is a deficient number, since it is larger than the sum of its proper divisors (571302717).

1281971979 is a wasteful number, since it uses less digits than its factorization.

1281971979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118266 (or 118263 counting only the distinct ones).

The product of its digits is 571536, while the sum is 54.

The square root of 1281971979 is about 35804.6362780018. The cubic root of 1281971979 is about 1086.3243412259.

The spelling of 1281971979 in words is "one billion, two hundred eighty-one million, nine hundred seventy-one thousand, nine hundred seventy-nine".