6999989 has 2 divisors, whose sum is σ = 6999990. Its totient is φ = 6999988.

The previous prime is 6999973. The next prime is 6999997. The reversal of 6999989 is 9899996.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5880625 + 1119364 = 2425^2 + 1058^2 .

It is a cyclic number.

It is not a de Polignac number, because 6999989 - 2⁴ = 6999973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6999929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3499994 + 3499995.

It is an arithmetic number, because the mean of its divisors is an integer number (3499995).

Almost surely, 2^6999989 is an apocalyptic number.

It is an amenable number.

6999989 is a deficient number, since it is larger than the sum of its proper divisors (1).

6999989 is an equidigital number, since it uses as much as digits as its factorization.

6999989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2834352, while the sum is 59.

The square root of 6999989 is about 2645.7492322592. The cubic root of 6999989 is about 191.2930180760.

It can be divided in two parts, 699998 and 9, that added together give a palindrome (700007).

The spelling of 6999989 in words is "six million, nine hundred ninety-nine thousand, nine hundred eighty-nine".