646953399 has 40 divisors (see below), whose sum is σ = 1000340880. Its totient is φ = 416358144.

The previous prime is 646953397. The next prime is 646953409. The reversal of 646953399 is 993359646.

It is not a de Polignac number, because 646953399 - 2¹ = 646953397 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646953397) 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 39 ways as a sum of consecutive naturals, for example, 415807 + ... + 417359.

It is an arithmetic number, because the mean of its divisors is an integer number (25008522).

Almost surely, 2^646953399 is an apocalyptic number.

646953399 is a deficient number, since it is larger than the sum of its proper divisors (353387481).

646953399 is a wasteful number, since it uses less digits than its factorization.

646953399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1741 (or 1732 counting only the distinct ones).

The product of its digits is 4723920, while the sum is 54.

The square root of 646953399 is about 25435.2786302804. The cubic root of 646953399 is about 864.8836084721.

The spelling of 646953399 in words is "six hundred forty-six million, nine hundred fifty-three thousand, three hundred ninety-nine".