208440031 has 2 divisors, whose sum is σ = 208440032. Its totient is φ = 208440030.

The previous prime is 208440017. The next prime is 208440059. The reversal of 208440031 is 130044802.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 208440031 - 2²¹ = 206342879 is a prime.

It is a super-2 number, since 2×208440031² = 86894493046561922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 208439984 and 208440011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208440131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104220015 + 104220016.

It is an arithmetic number, because the mean of its divisors is an integer number (104220016).

Almost surely, 2^208440031 is an apocalyptic number.

208440031 is a deficient number, since it is larger than the sum of its proper divisors (1).

208440031 is an equidigital number, since it uses as much as digits as its factorization.

208440031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 208440031 is about 14437.4523722158. The cubic root of 208440031 is about 592.9167367339.

Adding to 208440031 its reverse (130044802), we get a palindrome (338484833).

The spelling of 208440031 in words is "two hundred eight million, four hundred forty thousand, thirty-one".