649999993 has 2 divisors, whose sum is σ = 649999994. Its totient is φ = 649999992.

The previous prime is 649999921. The next prime is 650000009. The reversal of 649999993 is 399999946.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 639482944 + 10517049 = 25288^2 + 3243^2 .

It is a cyclic number.

It is not a de Polignac number, because 649999993 - 2¹³ = 649991801 is a prime.

It is not a weakly prime, because it can be changed into another prime (649999193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324999996 + 324999997.

It is an arithmetic number, because the mean of its divisors is an integer number (324999997).

Almost surely, 2^649999993 is an apocalyptic number.

It is an amenable number.

649999993 is a deficient number, since it is larger than the sum of its proper divisors (1).

649999993 is an equidigital number, since it uses as much as digits as its factorization.

649999993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38263752, while the sum is 67.

The square root of 649999993 is about 25495.0974306826. The cubic root of 649999993 is about 866.2391022313.

The spelling of 649999993 in words is "six hundred forty-nine million, nine hundred ninety-nine thousand, nine hundred ninety-three".