649922591 has 4 divisors (see below), whose sum is σ = 650098800. Its totient is φ = 649746384.

The previous prime is 649922549. The next prime is 649922599. The reversal of 649922591 is 195229946.

It is a happy number.

649922591 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 649922591 - 2⁶ = 649922527 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 (649922599) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82451 + ... + 89988.

It is an arithmetic number, because the mean of its divisors is an integer number (162524700).

Almost surely, 2^649922591 is an apocalyptic number.

649922591 is a deficient number, since it is larger than the sum of its proper divisors (176209).

649922591 is a wasteful number, since it uses less digits than its factorization.

649922591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176208.

The product of its digits is 349920, while the sum is 47.

The square root of 649922591 is about 25493.5794073724. The cubic root of 649922591 is about 866.2047169486.

The spelling of 649922591 in words is "six hundred forty-nine million, nine hundred twenty-two thousand, five hundred ninety-one".