163664649 has 6 divisors (see below), whose sum is σ = 236404506. Its totient is φ = 109109760.

The previous prime is 163664639. The next prime is 163664659. The reversal of 163664649 is 946466361.

163664649 is a `hidden beast` number, since 1 + 636 + 6 + 4 + 6 + 4 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (163664639) and next prime (163664659).

It can be written as a sum of positive squares in only one way, i.e., 119508624 + 44156025 = 10932^2 + 6645^2 .

It is not a de Polignac number, because 163664649 - 2⁵ = 163664617 is a prime.

It is a super-2 number, since 2×163664649² = 53572234664586402, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (163664609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9092472 + ... + 9092489.

It is an arithmetic number, because the mean of its divisors is an integer number (39400751).

Almost surely, 2^163664649 is an apocalyptic number.

It is an amenable number.

163664649 is a deficient number, since it is larger than the sum of its proper divisors (72739857).

163664649 is a wasteful number, since it uses less digits than its factorization.

163664649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18184967 (or 18184964 counting only the distinct ones).

The product of its digits is 559872, while the sum is 45.

The square root of 163664649 is about 12793.1485178591. The cubic root of 163664649 is about 546.9970210181.

The spelling of 163664649 in words is "one hundred sixty-three million, six hundred sixty-four thousand, six hundred forty-nine".