87819440 has 20 divisors (see below), whose sum is σ = 204180384. Its totient is φ = 35127744.

The previous prime is 87819437. The next prime is 87819449. The reversal of 87819440 is 4491878.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (87819449) 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, 548792 + ... + 548951.

Almost surely, 2^87819440 is an apocalyptic number.

87819440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

87819440 is an abundant number, since it is smaller than the sum of its proper divisors (116360944).

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

87819440 is a wasteful number, since it uses less digits than its factorization.

87819440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1097756 (or 1097750 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 41.

The square root of 87819440 is about 9371.2026976264. The cubic root of 87819440 is about 444.4915962937.

The spelling of 87819440 in words is "eighty-seven million, eight hundred nineteen thousand, four hundred forty".