649021673 has 4 divisors (see below), whose sum is σ = 669957888. Its totient is φ = 628085460.

The previous prime is 649021651. The next prime is 649021691. The reversal of 649021673 is 376120946.

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, and also an emirpimes, since its reverse is a distinct semiprime: 376120946 = 2 ⋅188060473.

It is a cyclic number.

It is not a de Polignac number, because 649021673 - 2¹⁴ = 649005289 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (649021693) 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, 10468061 + ... + 10468122.

It is an arithmetic number, because the mean of its divisors is an integer number (167489472).

Almost surely, 2^649021673 is an apocalyptic number.

It is an amenable number.

649021673 is a deficient number, since it is larger than the sum of its proper divisors (20936215).

649021673 is a wasteful number, since it uses less digits than its factorization.

649021673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20936214.

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 649021673 is about 25475.9037719960. The cubic root of 649021673 is about 865.8042896283.

The spelling of 649021673 in words is "six hundred forty-nine million, twenty-one thousand, six hundred seventy-three".