406865989 has 2 divisors, whose sum is σ = 406865990. Its totient is φ = 406865988.

The previous prime is 406865983. The next prime is 406866029. The reversal of 406865989 is 989568604.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 259049025 + 147816964 = 16095^2 + 12158^2 .

It is a cyclic number.

It is not a de Polignac number, because 406865989 - 2⁷ = 406865861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (406865983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203432994 + 203432995.

It is an arithmetic number, because the mean of its divisors is an integer number (203432995).

Almost surely, 2^406865989 is an apocalyptic number.

It is an amenable number.

406865989 is a deficient number, since it is larger than the sum of its proper divisors (1).

406865989 is an equidigital number, since it uses as much as digits as its factorization.

406865989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3732480, while the sum is 55.

The square root of 406865989 is about 20170.9193890611. The cubic root of 406865989 is about 740.9981593441.

The spelling of 406865989 in words is "four hundred six million, eight hundred sixty-five thousand, nine hundred eighty-nine".