649921799 has 2 divisors, whose sum is σ = 649921800. Its totient is φ = 649921798.

The previous prime is 649921751. The next prime is 649921807. The reversal of 649921799 is 997129946.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-649921799 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (649921739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 324960899 + 324960900.

It is an arithmetic number, because the mean of its divisors is an integer number (324960900).

Almost surely, 2^649921799 is an apocalyptic number.

649921799 is a deficient number, since it is larger than the sum of its proper divisors (1).

649921799 is an equidigital number, since it uses as much as digits as its factorization.

649921799 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2204496, while the sum is 56.

The square root of 649921799 is about 25493.5638740448. The cubic root of 649921799 is about 866.2043650942.

The spelling of 649921799 in words is "six hundred forty-nine million, nine hundred twenty-one thousand, seven hundred ninety-nine".