40143989 has 2 divisors, whose sum is σ = 40143990. Its totient is φ = 40143988.

The previous prime is 40143967. The next prime is 40143991. The reversal of 40143989 is 98934104.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21696964 + 18447025 = 4658^2 + 4295^2 .

It is a cyclic number.

It is not a de Polignac number, because 40143989 - 2¹² = 40139893 is a prime.

It is a super-2 number, since 2×40143989² = 3223079705664242, which contains 22 as substring.

Together with 40143991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40143289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20071994 + 20071995.

It is an arithmetic number, because the mean of its divisors is an integer number (20071995).

Almost surely, 2^40143989 is an apocalyptic number.

It is an amenable number.

40143989 is a deficient number, since it is larger than the sum of its proper divisors (1).

40143989 is an equidigital number, since it uses as much as digits as its factorization.

40143989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 40143989 is about 6335.9284244695. The cubic root of 40143989 is about 342.4050607975.

The spelling of 40143989 in words is "forty million, one hundred forty-three thousand, nine hundred eighty-nine".