3661869 has 4 divisors (see below), whose sum is σ = 4882496. Its totient is φ = 2441244.

The previous prime is 3661841. The next prime is 3661871. The reversal of 3661869 is 9681663.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9681663 = 3 ⋅3227221.

It is a de Polignac number, because none of the positive numbers 2^k-3661869 is a prime.

It is a super-2 number, since 2×3661869² = 26818569146322, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3661369) 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, 610309 + ... + 610314.

It is an arithmetic number, because the mean of its divisors is an integer number (1220624).

Almost surely, 2^3661869 is an apocalyptic number.

It is an amenable number.

3661869 is a deficient number, since it is larger than the sum of its proper divisors (1220627).

3661869 is a wasteful number, since it uses less digits than its factorization.

3661869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1220626.

The product of its digits is 46656, while the sum is 39.

The square root of 3661869 is about 1913.6010556017. The cubic root of 3661869 is about 154.1348821091.

The spelling of 3661869 in words is "three million, six hundred sixty-one thousand, eight hundred sixty-nine".