210220649 has 4 divisors (see below), whose sum is σ = 210422100. Its totient is φ = 210019200.

The previous prime is 210220639. The next prime is 210220663. The reversal of 210220649 is 946022012.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 139122025 + 71098624 = 11795^2 + 8432^2 .

It is a cyclic number.

It is not a de Polignac number, because 210220649 - 2²⁴ = 193443433 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (210220639) 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, 99152 + ... + 101249.

It is an arithmetic number, because the mean of its divisors is an integer number (52605525).

Almost surely, 2^210220649 is an apocalyptic number.

It is an amenable number.

210220649 is a deficient number, since it is larger than the sum of its proper divisors (201451).

210220649 is a wasteful number, since it uses less digits than its factorization.

210220649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201450.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 210220649 is about 14498.9878612267. The cubic root of 210220649 is about 594.6003002542.

The spelling of 210220649 in words is "two hundred ten million, two hundred twenty thousand, six hundred forty-nine".