209521149 has 8 divisors (see below), whose sum is σ = 279593760. Its totient is φ = 139564656.

The previous prime is 209521139. The next prime is 209521181. The reversal of 209521149 is 941125902.

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

It is not a de Polignac number, because 209521149 - 2⁷ = 209521021 is a prime.

It is a super-2 number, since 2×209521149² = 87798223756560402, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209521139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24727 + ... + 32100.

It is an arithmetic number, because the mean of its divisors is an integer number (34949220).

Almost surely, 2^209521149 is an apocalyptic number.

It is an amenable number.

209521149 is a deficient number, since it is larger than the sum of its proper divisors (70072611).

209521149 is a wasteful number, since it uses less digits than its factorization.

209521149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58059.

The product of its (nonzero) digits is 6480, while the sum is 33.

The square root of 209521149 is about 14474.8453877753. The cubic root of 209521149 is about 593.9400652607.

The spelling of 209521149 in words is "two hundred nine million, five hundred twenty-one thousand, one hundred forty-nine".