551664989 has 2 divisors, whose sum is σ = 551664990. Its totient is φ = 551664988.

The previous prime is 551664937. The next prime is 551665003. The reversal of 551664989 is 989466155.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 544428889 + 7236100 = 23333^2 + 2690^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-551664989 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 551664989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (551663989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 275832494 + 275832495.

It is an arithmetic number, because the mean of its divisors is an integer number (275832495).

Almost surely, 2^551664989 is an apocalyptic number.

It is an amenable number.

551664989 is a deficient number, since it is larger than the sum of its proper divisors (1).

551664989 is an equidigital number, since it uses as much as digits as its factorization.

551664989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2332800, while the sum is 53.

The square root of 551664989 is about 23487.5496593408. The cubic root of 551664989 is about 820.1472019098.

The spelling of 551664989 in words is "five hundred fifty-one million, six hundred sixty-four thousand, nine hundred eighty-nine".