3666551 has 4 divisors (see below), whose sum is σ = 4190352. Its totient is φ = 3142752.

The previous prime is 3666539. The next prime is 3666581. The reversal of 3666551 is 1556663.

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

It is a cyclic number.

It is not a de Polignac number, because 3666551 - 2¹⁰ = 3665527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3666521) 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, 261890 + ... + 261903.

It is an arithmetic number, because the mean of its divisors is an integer number (1047588).

Almost surely, 2^3666551 is an apocalyptic number.

3666551 is a deficient number, since it is larger than the sum of its proper divisors (523801).

3666551 is an equidigital number, since it uses as much as digits as its factorization.

3666551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 523800.

The product of its digits is 16200, while the sum is 32.

The square root of 3666551 is about 1914.8240128012. The cubic root of 3666551 is about 154.2005454966.

The spelling of 3666551 in words is "three million, six hundred sixty-six thousand, five hundred fifty-one".