649709539 has 2 divisors, whose sum is σ = 649709540. Its totient is φ = 649709538.

The previous prime is 649709537. The next prime is 649709573. The reversal of 649709539 is 935907946.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 649709539 - 2¹ = 649709537 is a prime.

Together with 649709537, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (649709537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324854769 + 324854770.

It is an arithmetic number, because the mean of its divisors is an integer number (324854770).

Almost surely, 2^649709539 is an apocalyptic number.

649709539 is a deficient number, since it is larger than the sum of its proper divisors (1).

649709539 is an equidigital number, since it uses as much as digits as its factorization.

649709539 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1837080, while the sum is 52.

The square root of 649709539 is about 25489.4005225702. The cubic root of 649709539 is about 866.1100560259.

The spelling of 649709539 in words is "six hundred forty-nine million, seven hundred nine thousand, five hundred thirty-nine".