3561820 has 12 divisors (see below), whose sum is σ = 7479864. Its totient is φ = 1424720.

The previous prime is 3561799. The next prime is 3561827. The reversal of 3561820 is 281653.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3561827) 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, 89026 + ... + 89065.

It is an arithmetic number, because the mean of its divisors is an integer number (623322).

Almost surely, 2^3561820 is an apocalyptic number.

It is an amenable number.

3561820 is an abundant number, since it is smaller than the sum of its proper divisors (3918044).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3561820 is a wasteful number, since it uses less digits than its factorization.

3561820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178100 (or 178098 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 3561820 is about 1887.2784638203. The cubic root of 3561820 is about 152.7181505666.

The spelling of 3561820 in words is "three million, five hundred sixty-one thousand, eight hundred twenty".