111661279 has 2 divisors, whose sum is σ = 111661280. Its totient is φ = 111661278.

The previous prime is 111661273. The next prime is 111661337. The reversal of 111661279 is 972166111.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-111661279 is a prime.

It is equal to p_6392734 and since 111661279 and 6392734 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (111661273) 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 as a sum of consecutive naturals, namely, 55830639 + 55830640.

It is an arithmetic number, because the mean of its divisors is an integer number (55830640).

Almost surely, 2^111661279 is an apocalyptic number.

111661279 is a deficient number, since it is larger than the sum of its proper divisors (1).

111661279 is an equidigital number, since it uses as much as digits as its factorization.

111661279 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4536, while the sum is 34.

The square root of 111661279 is about 10566.9900634003. The cubic root of 111661279 is about 481.5420301206.

The spelling of 111661279 in words is "one hundred eleven million, six hundred sixty-one thousand, two hundred seventy-nine".