187149521 has 8 divisors (see below), whose sum is σ = 201659304. Its totient is φ = 172656000.

The previous prime is 187149517. The next prime is 187149541. The reversal of 187149521 is 125941781.

It can be written as a sum of positive squares in 4 ways, for example, as 103225600 + 83923921 = 10160^2 + 9161^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 187149521 - 2² = 187149517 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 (187149541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31271 + ... + 36771.

It is an arithmetic number, because the mean of its divisors is an integer number (25207413).

Almost surely, 2^187149521 is an apocalyptic number.

It is an amenable number.

187149521 is a deficient number, since it is larger than the sum of its proper divisors (14509783).

187149521 is a wasteful number, since it uses less digits than its factorization.

187149521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8131.

The product of its digits is 20160, while the sum is 38.

The square root of 187149521 is about 13680.2602679920. The cubic root of 187149521 is about 572.0002781308. Note that the first 3 decimals are identical.

The spelling of 187149521 in words is "one hundred eighty-seven million, one hundred forty-nine thousand, five hundred twenty-one".