646722166 has 8 divisors (see below), whose sum is σ = 971990640. Its totient is φ = 322725288.

The previous prime is 646722163. The next prime is 646722169. The reversal of 646722166 is 661227646.

It is an interprime number because it is at equal distance from previous prime (646722163) and next prime (646722169).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646722163) 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, 316626 + ... + 318661.

It is an arithmetic number, because the mean of its divisors is an integer number (121498830).

Almost surely, 2^646722166 is an apocalyptic number.

646722166 is a deficient number, since it is larger than the sum of its proper divisors (325268474).

646722166 is a wasteful number, since it uses less digits than its factorization.

646722166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 635798.

The product of its digits is 145152, while the sum is 40.

The square root of 646722166 is about 25430.7327067074. The cubic root of 646722166 is about 864.7805544432.

The spelling of 646722166 in words is "six hundred forty-six million, seven hundred twenty-two thousand, one hundred sixty-six".