43139917 has 2 divisors, whose sum is σ = 43139918. Its totient is φ = 43139916.

The previous prime is 43139867. The next prime is 43139923. The reversal of 43139917 is 71993134.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39702601 + 3437316 = 6301^2 + 1854^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-43139917 is a prime.

It is a super-2 number, since 2×43139917² = 3722104877533778, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43139977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21569958 + 21569959.

It is an arithmetic number, because the mean of its divisors is an integer number (21569959).

Almost surely, 2^43139917 is an apocalyptic number.

It is an amenable number.

43139917 is a deficient number, since it is larger than the sum of its proper divisors (1).

43139917 is an equidigital number, since it uses as much as digits as its factorization.

43139917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20412, while the sum is 37.

The square root of 43139917 is about 6568.0984310529. The cubic root of 43139917 is about 350.7193829667.

The spelling of 43139917 in words is "forty-three million, one hundred thirty-nine thousand, nine hundred seventeen".