690069509 has 2 divisors, whose sum is σ = 690069510. Its totient is φ = 690069508.

The previous prime is 690069467. The next prime is 690069521. The reversal of 690069509 is 905960096.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 536061409 + 154008100 = 23153^2 + 12410^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-690069509 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 690069509.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (690069209) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345034754 + 345034755.

It is an arithmetic number, because the mean of its divisors is an integer number (345034755).

Almost surely, 2^690069509 is an apocalyptic number.

It is an amenable number.

690069509 is a deficient number, since it is larger than the sum of its proper divisors (1).

690069509 is an equidigital number, since it uses as much as digits as its factorization.

690069509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 131220, while the sum is 44.

The square root of 690069509 is about 26269.1741210111. The cubic root of 690069509 is about 883.6852637158.

The spelling of 690069509 in words is "six hundred ninety million, sixty-nine thousand, five hundred nine".