83561820 has 24 divisors (see below), whose sum is σ = 233973264. Its totient is φ = 22283136.

The previous prime is 83561801. The next prime is 83561831. The reversal of 83561820 is 2816538.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 696289 + ... + 696408.

It is an arithmetic number, because the mean of its divisors is an integer number (9748886).

Almost surely, 2^83561820 is an apocalyptic number.

It is an amenable number.

83561820 is an abundant number, since it is smaller than the sum of its proper divisors (150411444).

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

83561820 is a wasteful number, since it uses less digits than its factorization.

83561820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1392709 (or 1392707 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 83561820 is about 9141.2154552882. The cubic root of 83561820 is about 437.1890710496.

The spelling of 83561820 in words is "eighty-three million, five hundred sixty-one thousand, eight hundred twenty".