87402640 has 80 divisors (see below), whose sum is σ = 225985536. Its totient is φ = 31219200.

The previous prime is 87402613. The next prime is 87402643. The reversal of 87402640 is 4620478.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (87402643) 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, 30885 + ... + 33595.

Almost surely, 2^87402640 is an apocalyptic number.

87402640 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 87402640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (112992768).

87402640 is an abundant number, since it is smaller than the sum of its proper divisors (138582896).

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

87402640 is a wasteful number, since it uses less digits than its factorization.

87402640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2768 (or 2762 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 31.

The square root of 87402640 is about 9348.9379075914. The cubic root of 87402640 is about 443.7872800790.

The spelling of 87402640 in words is "eighty-seven million, four hundred two thousand, six hundred forty".