646632722 has 6 divisors (see below), whose sum is σ = 970003029. Its totient is φ = 323298380.

The previous prime is 646632697. The next prime is 646632731. The reversal of 646632722 is 227236646.

It can be written as a sum of positive squares in 2 ways, for example, as 371371441 + 275261281 = 19271^2 + 16591^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=17981.

It is a super-2 number, since 2×646632722² = 836267754322258568, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 26972 + ... + 44952.

Almost surely, 2^646632722 is an apocalyptic number.

646632722 is a deficient number, since it is larger than the sum of its proper divisors (323370307).

646632722 is an frugal number, since it uses more digits than its factorization.

646632722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35964 (or 17983 counting only the distinct ones).

The product of its digits is 145152, while the sum is 38.

The square root of 646632722 is about 25428.9740650306. The cubic root of 646632722 is about 864.7406851855.

The spelling of 646632722 in words is "six hundred forty-six million, six hundred thirty-two thousand, seven hundred twenty-two".