1247279161 has 4 divisors (see below), whose sum is σ = 1247393872. Its totient is φ = 1247164452.

The previous prime is 1247279147. The next prime is 1247279179. The reversal of 1247279161 is 1619727421.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1247279161 - 2²³ = 1238890553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1247279461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39111 + ... + 63436.

It is an arithmetic number, because the mean of its divisors is an integer number (311848468).

Almost surely, 2^1247279161 is an apocalyptic number.

It is an amenable number.

1247279161 is a deficient number, since it is larger than the sum of its proper divisors (114711).

1247279161 is a wasteful number, since it uses less digits than its factorization.

1247279161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114710.

The product of its digits is 42336, while the sum is 40.

The square root of 1247279161 is about 35316.8396236130. The cubic root of 1247279161 is about 1076.4351945894.

The spelling of 1247279161 in words is "one billion, two hundred forty-seven million, two hundred seventy-nine thousand, one hundred sixty-one".