646675971 has 16 divisors (see below), whose sum is σ = 914004000. Its totient is φ = 405291008.

The previous prime is 646675927. The next prime is 646675979. The reversal of 646675971 is 179576646.

It is a happy number.

646675971 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 646675971 - 2¹³ = 646667779 is a prime.

It is a super-2 number, since 2×646675971² = 836379622937585682, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (646675979) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40555 + ... + 54203.

It is an arithmetic number, because the mean of its divisors is an integer number (57125250).

Almost surely, 2^646675971 is an apocalyptic number.

646675971 is a deficient number, since it is larger than the sum of its proper divisors (267328029).

646675971 is a wasteful number, since it uses less digits than its factorization.

646675971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14598.

The product of its digits is 1905120, while the sum is 51.

The square root of 646675971 is about 25429.8244390322. The cubic root of 646675971 is about 864.7599636903.

The spelling of 646675971 in words is "six hundred forty-six million, six hundred seventy-five thousand, nine hundred seventy-one".