87070821 has 16 divisors (see below), whose sum is σ = 123235200. Its totient is φ = 54494208.

The previous prime is 87070813. The next prime is 87070831. The reversal of 87070821 is 12807078.

It is not a de Polignac number, because 87070821 - 2³ = 87070813 is a prime.

It is a super-2 number, since 2×87070821² = 15162655739228082, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87070811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20445 + ... + 24333.

It is an arithmetic number, because the mean of its divisors is an integer number (7702200).

Almost surely, 2^87070821 is an apocalyptic number.

It is an amenable number.

87070821 is a deficient number, since it is larger than the sum of its proper divisors (36164379).

87070821 is a wasteful number, since it uses less digits than its factorization.

87070821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4348.

The product of its (nonzero) digits is 6272, while the sum is 33.

The square root of 87070821 is about 9331.1746848936. The cubic root of 87070821 is about 443.2249637445.

Adding to 87070821 its reverse (12807078), we get a palindrome (99877899).

The spelling of 87070821 in words is "eighty-seven million, seventy thousand, eight hundred twenty-one".