43639081 has 2 divisors, whose sum is σ = 43639082. Its totient is φ = 43639080.

The previous prime is 43639061. The next prime is 43639091. The reversal of 43639081 is 18093634.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29800681 + 13838400 = 5459^2 + 3720^2 .

It is a cyclic number.

It is not a de Polignac number, because 43639081 - 2⁵ = 43639049 is a prime.

It is a super-2 number, since 2×43639081² = 3808738781049122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (43639061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21819540 + 21819541.

It is an arithmetic number, because the mean of its divisors is an integer number (21819541).

Almost surely, 2^43639081 is an apocalyptic number.

It is an amenable number.

43639081 is a deficient number, since it is larger than the sum of its proper divisors (1).

43639081 is an equidigital number, since it uses as much as digits as its factorization.

43639081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 43639081 is about 6605.9882682306. The cubic root of 43639081 is about 352.0669019918.

The spelling of 43639081 in words is "forty-three million, six hundred thirty-nine thousand, eighty-one".