649919797 has 4 divisors (see below), whose sum is σ = 657750240. Its totient is φ = 642089356.

The previous prime is 649919791. The next prime is 649919801. The reversal of 649919797 is 797919946.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 649919797 - 2³ = 649919789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649919791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3915097 + ... + 3915262.

It is an arithmetic number, because the mean of its divisors is an integer number (164437560).

Almost surely, 2^649919797 is an apocalyptic number.

It is an amenable number.

649919797 is a deficient number, since it is larger than the sum of its proper divisors (7830443).

649919797 is an equidigital number, since it uses as much as digits as its factorization.

649919797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7830442.

The product of its digits is 7715736, while the sum is 61.

The square root of 649919797 is about 25493.5246092022. The cubic root of 649919797 is about 866.2034756831.

The spelling of 649919797 in words is "six hundred forty-nine million, nine hundred nineteen thousand, seven hundred ninety-seven".