105991979 has 2 divisors, whose sum is σ = 105991980. Its totient is φ = 105991978.

The previous prime is 105991961. The next prime is 105991987. The reversal of 105991979 is 979199501.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-105991979 is a prime.

It is a super-2 number, since 2×105991979² = 22468599224672882, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (105991999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52995989 + 52995990.

It is an arithmetic number, because the mean of its divisors is an integer number (52995990).

Almost surely, 2^105991979 is an apocalyptic number.

105991979 is a deficient number, since it is larger than the sum of its proper divisors (1).

105991979 is an equidigital number, since it uses as much as digits as its factorization.

105991979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 229635, while the sum is 50.

The square root of 105991979 is about 10295.2405994226. The cubic root of 105991979 is about 473.2504115910.

The spelling of 105991979 in words is "one hundred five million, nine hundred ninety-one thousand, nine hundred seventy-nine".