87820820 has 12 divisors (see below), whose sum is σ = 184423764. Its totient is φ = 35128320.

The previous prime is 87820819. The next prime is 87820847. The reversal of 87820820 is 2802878.

It can be written as a sum of positive squares in 2 ways, for example, as 51868804 + 35952016 = 7202^2 + 5996^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2195501 + ... + 2195540.

It is an arithmetic number, because the mean of its divisors is an integer number (15368647).

Almost surely, 2^87820820 is an apocalyptic number.

It is an amenable number.

87820820 is an abundant number, since it is smaller than the sum of its proper divisors (96602944).

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

87820820 is a wasteful number, since it uses less digits than its factorization.

87820820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4391050 (or 4391048 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 35.

The square root of 87820820 is about 9371.2763271606. The cubic root of 87820820 is about 444.4939245375.

The spelling of 87820820 in words is "eighty-seven million, eight hundred twenty thousand, eight hundred twenty".