87640000 has 140 divisors (see below), whose sum is σ = 249157744. Its totient is φ = 29952000.

The previous prime is 87639983. The next prime is 87640009. The reversal of 87640000 is 4678.

It is a tau number, because it is divible by the number of its divisors (140).

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87640009) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 279844 + ... + 280156.

Almost surely, 2^87640000 is an apocalyptic number.

87640000 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 87640000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124578872).

87640000 is an abundant number, since it is smaller than the sum of its proper divisors (161517744).

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

87640000 is an equidigital number, since it uses as much as digits as its factorization.

87640000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352 (or 327 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 87640000 is about 9361.6237907748. The cubic root of 87640000 is about 444.1886491042.

Adding to 87640000 its reverse (4678), we get a palindrome (87644678).

The spelling of 87640000 in words is "eighty-seven million, six hundred forty thousand".